Sherry Crentsil
STRATEGIC TRANSFORMATION · COMPLEX DELIVERY · EXECUTIVE LEADERSHIP

Transformation leadership for complex, business-critical change.

Fifteen years inside banks and lenders. I am brought into programmes already moving, where the real question is whether the evidence supports the confidence.

0Years leading complex transformation
0M&A integration led, combined value
0Sectors across banking and lending
Selected programmes
  • M&A integrationKensington Mortgage Company
  • Banking integrationTesco Bank
  • Amazon's first UK personal credit cardAmazon Barclaycard
  • Online mortgage platform and Apple Pay adoptionSantander

Most transformations do not fail quietly.
They fail while reporting progress.

THE MEASUREMENT ALMOST NOBODY TAKES
THE PRODUCT

Transformation Recovery OS

An evidence-led methodology for separating reported progress from demonstrated readiness, diagnosing root causes and identifying the interventions with the greatest leverage.

Transformation Recovery OSReport
DecisionProceed With ConditionsAuthorised now
Executive decision brief
Condition 12Entry gate
Evidence basis and limitations
Eight sections1
TWO ASSESSMENTS, TWO AUDIENCES

Choose the assessment
for your seat at the table.

Both produce the same eight-section report and an assessment recommendation. The difference is who answers.

Professional Diagnostic

Pressure-test your programme before the next executive review.

For Programme Directors, Transformation Leads, Programme Managers, Delivery Leads, PMO Leaders and Independent Consultants.

How it works You answer for your own programme. The report tests whether the evidence you hold supports the confidence being reported.

Organisation Assessment

Know whether a critical transformation is genuinely under control.

For Sponsors, portfolio leaders and organisations assessing material transformation exposure.

How it works Two respondents answer independently. Their accounts are reconciled, and where they differ the report shows what each recorded rather than choosing between them.

WHAT EVERY REPORT CONTAINS
  1. Executive decision brief
  2. Decision rationale and authorised scope
  3. Material findings
  4. Leading constraint hypothesis
  5. Conditions and controls
  6. Strengths to protect
  7. Evidence basis and limitations
  8. Sources considered
WHY TRUST IT

Built to be checked,
not just believed.

Every consultancy that diagnoses a troubled programme has a natural next sale: the remediation. This one has none. The same answers produce the same output, every time. Nothing is generated fresh, so nothing can drift.

The judgement comes from fifteen years of experience, written down as rules.

BEYOND THE REPORT

When a report is not enough,
I work inside the programme.

Sherry Crentsil listening in a meeting

Is your programme green
because of evidence?

ABOUT

I kept finding the same gap, so I built something to look for it.

Fifteen years leading complex transformation, and one question that has never stopped being useful.

Sherry Crentsil

MA Management · MSc Accounting and Finance
Certified Scrum Master · Certified Product Owner · PRINCE2

I am usually brought into programmes that are already moving. Sometimes they are going well. Sometimes the reporting says they are going well.

The first thing I do is read everything. Then I sit with the team and ask them to tell me about the project, without mentioning that I have read any of it.

The distance between what the documents claim and what the team says out loud is usually the whole diagnosis.

What I keep finding

It is rarely one dramatic failure. It is almost always something material that nobody thought to check, sitting quietly underneath a status that says everything is fine.

A downstream team that was never told the change was coming. A specialist everyone assumes is available who is committed elsewhere. A risk carried forward so many times it has stopped being read.

Sherry Crentsil in a meeting

Why I built Transformation Recovery OS

For most of my career I wanted something that would work alongside me. Not something that agreed with me. Something that would question me, and challenge the answers I had accepted a little too easily.

A programme is amber, but there is a deadline and a real belief it can be turned around, so it is reported as green. Nobody is lying. The status is reflecting hope rather than evidence.

I wanted something anyone leading a programme could use on a Tuesday afternoon.

Built from experience, with AI as a tool.

Transformation Recovery OS comes from my experience and knowledge: fifteen years inside complex programmes, and the judgement that comes with it.

I keep developing and move with the times, which is why I work with AI, and why I built this website and the product with it.

A transformation leader who is fluent in AI and rigorous about evidence: that is the combination on offer.

How it should be used

This works from what you tell it, so it is built to be used honestly. Answer it the way you would answer somebody you had hired to find the problem.

It attaches no probability to anything, and that is deliberate. There is no percentage likelihood of failure and no risk score presented as a forecast, because no such number could be defended.

Sherry Crentsil
SELECTED TRANSFORMATION EXPERIENCE

Experience across complex, business-critical transformation.

MA Management · MSc Accounting and Finance · Certified Scrum Master · Certified Product Owner · PRINCE2

My experience spans complex transformation across lending, payments, mortgages, M&A integration, regulatory change and enterprise platforms.

FLAGSHIP SELECTED EXPERIENCE

Lending & Risk Platform Transformation

EXAMPLE: ACBS → LOANIQ MIGRATION

Outcome: Reduced processing times and integration costs across a multi-billion-pound lending portfolio.

Context: A complex lending-platform transition from legacy ACBS to LoanIQ requiring attention to data integrity, phased delivery, specialist capability, testing, business continuity and downstream reporting.

Delivery focus: I focused on the conditions required for end-to-end assurance, including reconciliation, reporting, operational readiness and the ability of downstream consumers to use accurate information.

Methodology informed: Data integrity · End-to-end assurance · Reporting · Testing · Capability · Readiness
PUBLIC CONTEXT · SOURCE: FINTECH FUTURESView public reference ↗

M&A Integration

EXAMPLE: KENSINGTON MORTGAGE COMPANY

Outcome: Part of Barclays' £2.3bn acquisition of Kensington Mortgage Company, completed March 2023.

Context: A large acquisition integration involving technology, operations, governance, dependencies and business integration across multiple workstreams.

Delivery focus: I worked across organisational boundaries to strengthen ownership, dependencies and executive decision-making where individual workstream success alone could not guarantee the overall integration outcome.

Methodology informed: M&A integration · Governance · Dependencies · Critical path · Executive decisions
PUBLIC CONTEXT · SOURCE: KENSINGTON MORTGAGESView public reference ↗

Banking Integration

EXAMPLE: TESCO BANK

Outcome: Part of Barclays' acquisition of Tesco Bank's retail banking business, completed November 2024.

Context: Integration of acquired Tesco Bank retail-banking operations and associated technology, operational processes and business dependencies.

Delivery focus: I coordinated across organisational boundaries, systems, customers, operational readiness and integration governance.

Methodology informed: Integration governance · Operational readiness · Dependencies · Customer continuity · Process continuity
PUBLIC CONTEXT · SOURCE: BARCLAYSView public reference ↗

Payments & Consumer Banking

EXAMPLE: AMAZON BARCLAYCARD

Outcome: Amazon's first personal credit card in the UK, launched August 2024.

Context: A major consumer-banking transformation programme including the launch of the Amazon Barclaycard in partnership with Amazon.

Delivery focus: I worked across technology delivery, customer journeys, operational readiness, governance and multiple teams within a complex regulated environment.

Methodology informed: Technology delivery · Customer journeys · Operational readiness · Governance · Complex regulated environments
PUBLIC CONTEXT · SOURCE: AMAZON / BARCLAYSView public reference ↗

Regulatory & Reporting Transformation

EXAMPLE: LIBOR

Outcome: Delivered full compliance with global central bank mandates, as part of an industry-wide transition that saw the final LIBOR rates cease publication in September 2024.

Context: Complex regulatory and reporting environments where controls, evidence, materiality, governance and accurate downstream information were essential.

Delivery focus: I focused on reporting integrity, control evidence, materiality and the governance required to support accurate downstream outcomes.

Methodology informed: Materiality · Reporting integrity · Evidence · Governance · Controls
PUBLIC CONTEXT · SOURCE: FCAView public reference ↗

Digital Lending & Customer Experience

EXAMPLE: SANTANDER DIGITAL MORTGAGE PLATFORM

Outcome: Cut application time to 30 minutes with an instant decision, lifting online applications by 15% and total applications processed by 20%. Santander has since been named Best Online Mortgage Provider by Moneyfacts.

Context: Santander's online mortgage application platform (the first of its kind in the UK), including online decisions in principle and eligible online application journeys, built on AWS with an Agile delivery model.

Delivery focus: I led development and launch of the platform, working across technology delivery, customer journey design and operational readiness to bring a fully digital, end-to-end mortgage application to market.

Methodology informed: Customer journeys · Digital delivery · Operational readiness · Lending decisions
PUBLIC CONTEXT · SOURCE: SANTANDER UKView public reference ↗
ADDITIONAL SELECTED EXPERIENCE

Delivery experience supporting Santander's adoption of Apple Pay as part of the bank's digital payments capability.

Methodology informed: Customer journeys · Digital payments · Operational readiness · Governance
PUBLIC CONTEXT · SOURCE: MACRUMORSView public reference ↗

Transformation and delivery experience across Cheques, Faster Payments, CHAPS and International Transactions.

Methodology informed: Payments infrastructure · Customer outcomes · Operational readiness · Governance

Transformation of a previously manual regulatory-reporting process through greater automation, control and delivery discipline.

Outcome: Cut execution time by 43%, moving a 2.5-week manual cycle to an automated solution and eliminating manual error in submissions.

Methodology informed: Process bottlenecks · Reporting integrity · Automation · Controls · Readiness

Delivery of data and technology change involving platform modernisation, APIs, reporting infrastructure and operational processes within a regulated financial-services environment.

Outcome: Improved reporting accuracy by 25% through a new collections and recoveries repository with new front-end tracking screens. Separately, migrated corporate risk models to cloud-based data lake infrastructure, improving system uptime and reporting speed by 20% and saving £500k+ in third-party costs.

Methodology informed: Data infrastructure · APIs · Reporting integrity · Operational processes · Governance

Interconnected Treasury, Risk and Finance platforms requiring systems thinking, complex dependency management, specialist capability and strong governance. I worked across platform dependencies, capability, governance and end-to-end delivery conditions.

Methodology informed: Systems thinking · Capability · Dependencies · Governance · End-to-end delivery
EXPERIENCE INTO METHODOLOGY

Experience translated into methodology.

The recurring delivery patterns across many years and many programmes, not any one of them, informed the questions, failure patterns and intervention logic within Transformation Recovery OS.

INSIGHTS / CATEGORY

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14 August 2026 · 6 minute read

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Transformation thinking for complex delivery.

Practical analysis of the evidence behind delivery confidence, readiness, governance and recovery.

Sherry Crentsil
Work With Me

Choose the level of support your transformation requires.

Some organisations need structured self-service assessment. Others require independent executive challenge or hands-on transformation leadership. The right route depends on the situation.

Start with Transformation Recovery OS

Transformation Recovery OS lets you assess transformation exposure independently before deciding whether deeper intervention is required.

Executive transformation support

DIRECT LEADERSHIP

Interim / Fractional Transformation Leadership

BEST WHEN

The programme needs accountable senior leadership inside the delivery system for a defined period.

INDEPENDENT REVIEW

Executive Recovery Review

BEST WHEN

An executive decision is approaching and confidence in delivery needs independent challenge.

Typical focus

  • Confidence in delivery, and capability
  • Governance and dependencies
  • Data and reporting integrity
  • Readiness, and where to intervene first
ONGOING ASSURANCE

Independent Programme Assurance

BEST WHEN

Sponsors need recurring independent visibility of delivery exposure and evidence quality over time.

Whichever route fits, the assessment is the place to start.

TRANSFORMATION RECOVERY OS / BY SHERRY CRENTSIL

Your transformation may be reporting progress. But can the evidence support the confidence?

Transformation Recovery OS is an evidence-led decision and recovery methodology for complex programmes where conventional status reporting is not enough to determine whether the intended outcome is genuinely secure.

Transformation Recovery OSReport
DecisionProceed With Conditions
Material findings
Condition 7Continuing control
Conditions and controls
HOW IT THINKS

The same five moves, every time.

Assess
Examine the evidence a programme is actually standing on.
Challenge
Test what the programme is asserting against that evidence.
Diagnose
Find the root cause behind the visible symptoms.
Prioritise
Identify where intervention has the greatest leverage.
Decide
Protect the business outcome, not just the plan.
WHAT IT DECIDES

Every assessment resolves to one of six states.

  1. Proceed
  2. Proceed With Conditions
  3. Pause
  4. Recover
  5. Rescope
  6. Strategic Reconsideration
WHAT MAKES IT DIFFERENT
TYPICAL STATUS-LED REVIEW
TRANSFORMATION RECOVERY OS
Primarily reports status
Challenges status against evidence
Logs issues
Distinguishes cause from consequence
Relies on RAG or summary confidence
Supports an explicit decision state
Recommends actions
Prioritises where intervention has the greatest leverage
TESTED AGAINST DOCUMENTED PROGRAMMES

Most methodologies ask you to trust them. This one shows its working.

UK government programmes across eleven sectors, assessed before their outcomes were known and benchmarked against the independent public record.

  • 11Sectors covered
  • NeverCalled a troubled programme healthy
  • NeverErred toward optimism
  • Every caseNamed an accountable owner
  • AlwaysSame evidence, same answer
CHOOSE YOUR ROUTE
For professionals

Professional Diagnostic

For people directly leading programmes.

For organisations

Organisation Assessment

For sponsors and organisations assessing material programmes.

Free entry point

What is already putting your transformation at risk?

A short check for early signals across delivery, capability, readiness and dependencies.

FREEEXPECTED COMPLETION: ~3 MINUTESNO CONFIDENTIAL DATA REQUIRED

Not knowing whether a material control or condition exists can itself be useful information. Select “Unsure” where you cannot confidently assess an area.

0 of 6 areas reviewed

Select one response in each area. Six answers, and you will know where to look first.

Diagnostic selection

Choose the assessment for your seat at the table.

Both routes ask the same thirty-nine questions and produce the same eight-section report and assessment recommendation. The difference is who answers: one person for their own programme, or two people independently, with their accounts reconciled.

The assessment is designed to test programme conditions without requiring commercially sensitive programme documents during the self-service assessment.

  1. 01Thirty-nine questions
  2. 02One or two respondents
  3. 03Eight-section report
Professional Diagnostic

Pressure-test your programme before the next executive review.

Best for

Someone directly leading or managing a programme.

Time needed: Set aside an hour. You can save and return at any point.

Audience

Programme Directors · Transformation Leads · Programme Managers · Delivery Leads · PMO Leaders · Independent Consultants

How it works

You answer for your own programme. The report tests whether the evidence you hold supports the confidence being reported, and states plainly where it does not.

Organisation Assessment

Know whether a critical transformation is genuinely under control.

Best for

Sponsors, portfolio leaders and organisations assessing material transformation exposure.

How it works

Two respondents answer independently. Their accounts are reconciled, and where they differ the report shows what each recorded rather than choosing between them. Where they agree, one consolidated report issues.

WHAT EVERY REPORT CONTAINS
  1. Executive decision brief
  2. Decision rationale and authorised scope
  3. Material findings
  4. Leading constraint hypothesis
  5. Conditions and controls
  6. Strengths to protect
  7. Evidence basis and limitations
  8. Sources considered
Report preview

This is what a report looks like.

A real report, from a synthetic assessment. Nothing here is a mock-up.

The decision
Decision
Proceed With Conditions
Authorised now
Commit the next tranche of funding for the platform.
Before stage entry
Stage entry must not proceed while any entry gate is open.
Four options weighed. One recommended.
Proceed without conditionsNot supported
Defer authorisationNot required at present
Stop or redesignNot supported at present

The bounded, reversible decision can be authorised while all six entry conditions are closed.

One of the six conditions

Entry gate 1: a completed evidence pack for every open condition

Current gap
No management response example was available and no document was offered for it.
Proof of closure
A dated, accepted record, agreed with the decision authority.
If not met
The authorised work does not start.
Validation

Most methodologies ask you to trust them. This one shows its working.

It was tested against major UK government transformation programmes across eleven sectors: each assessed at a fixed point before its outcome was known, with the expected answer written down and locked before the engine was run. Each was benchmarked against the independent public record of what actually happened, drawn from National Audit Office and Public Accounts Committee reporting published after the assessment date.

WHAT THE TESTING FOUND
SECTORS COVERED11
TIMES IT CALLED A TROUBLED PROGRAMME HEALTHYNever
TIMES IT ERRED TOWARD OPTIMISMNever
RECOMMENDATIONS NAMING AN ACCOUNTABLE OWNEREvery case
RECOMMENDATIONS NAMING A CONDITIONAL PATHEvery case
SAME EVIDENCE, SAME ANSWER, EVERY TIMEAlways

In not one case did the methodology conclude that a troubled programme was healthy. That is the error that costs money, and it did not occur.

On the headline decision it either agreed with the independent record or was more conservative, in every case, without exception.

AN EARLIER RESULT

TSB, 2018. Twelve days before go-live.

An earlier assessment examined TSB’s 2018 core banking migration at a fixed point twelve days before go-live, using only facts establishable at that date. The assessor did not know how it ended. Both the practitioner and the engine independently reached Pause. The migration went ahead; within hours customers were locked out, and the cost was approximately £366 million.

WHAT THE TESTING CHANGED

Two earlier versions were suspended by their own testing.

Version 1.0 was withdrawn after an assessment of Universal Credit exposed a defect in how it weighted causes by delivery stage. Version 1.1 was withdrawn after a deliberate positive control, running it against the London 2012 delivery programme, which succeeded, surfaced an over-caution defect before any client had seen the methodology. That failure was traced to a specific rule, corrected, and the correction tested against controlled probes before the version was frozen.

The standard applied is that a change to the methodology requires the same problem to appear twice, the full regression suite to pass, and every prior case to be re-run and explained.

SOURCES & REFERENCES

National Audit Office

Value-for-money reports on each programme assessed, used as the independent benchmark record.

National Audit Office ↗

Committee of Public Accounts

Parliamentary evidence sessions and reports, used where an NAO report was supplemented or followed up.

UK Parliament ↗

Slaughter and May Independent Review

Independent Review of TSB’s 2018 migration to a new IT platform (2019), referenced in section 5.

Slaughter and May ↗
Contact

Discuss a transformation challenge.

If you are leading a complex programme and need experienced transformation leadership, independent challenge or recovery support, get in touch.

Sherry Crentsil at her desk

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