Four Azure tenants.
One migration window.
Zero surprises.
A global asset management firm completed three regional acquisitions over 14 months. Each target ran its own Azure tenant, Active Directory forest, and M365 environment. When the board set an 18-week integration deadline, the IT team had one question: what exactly are we merging?
The answer required scanning infrastructure across four countries, two cloud regions, and three on-premises data centres — before a single migration task could be planned.
Engagement profile
The challenge
Three acquisitions closed in rapid succession, each negotiated independently. The due diligence teams had financials, contracts, and headcount — but no structured IT inventory for any of the acquired entities.
With an 18-week integration clock already running, the IT leadership team faced a decision familiar to anyone who has managed post-merger integration: start migrating on incomplete information, or spend weeks building an inventory manually before any migration work could begin.
No single inventory
Four separate IT teams managing four separate environments, none of whom had ever produced a complete asset register.
Hidden dependencies
Cross-tenant shared services, undocumented API integrations, and legacy application dependencies that would break during migration.
Compliance obligations
GDPR data residency constraints in EU entities, FCA requirements in the UK entity, and MAS obligations in Singapore.
47K+ identities
No master identity directory. Users existed in four separate forests with overlapping UPNs, group structures, and licence assignments.
18-week deadline
Board-mandated timeline was non-negotiable. The cost of overrun was estimated at £400K/week in duplicate infrastructure.
Limited discovery tooling
The team had spreadsheets, tribal knowledge, and basic Azure portal views. Nothing that could scan all four environments at once.
How ACQI was deployed
ACQI was deployed on Day 1 of the integration project, running across all four environments simultaneously. Discovery data flowed directly into migration planning — no manual handoff required.
Weeks 1–3
Discovery Sprint
Deployed ACQI across all four tenant environments simultaneously. 124 discovery modules executed in parallel across Azure, Active Directory, M365, and on-premises infrastructure.
Outputs
- 47,312 identities catalogued across all forests
- 340 applications fingerprinted and classified
- 12 undocumented legacy systems surfaced
- 1,847 orphaned accounts flagged for review
- 23 cross-tenant shared service dependencies mapped
Weeks 3–5
Risk & Dependency Analysis
ACQI's governance engine cross-referenced discovery data to identify migration blockers, compliance gaps, and technical dependencies that would have caused cutover failures.
Outputs
- 4 business-critical applications flagged as migration-blocking
- 16 conditional access policies with cross-tenant scope conflicts
- 3 AD trusts with undocumented service account dependencies
- GDPR data residency violations in 2 of 4 tenants
- Full risk heatmap exported for executive sign-off
Weeks 5–8
Wave-Based Migration Planning
Discovery intelligence fed directly into ACQI's migration planner. Users, mailboxes, and devices sorted into dependency-ordered waves. Go/No-Go gates enforced at each phase boundary.
Outputs
- 6 migration waves defined across 47K+ identities
- Critical path modelled with 3-day buffer at each gate
- Rollback procedures documented per wave
- Engineer scheduling completed for all 18 weeks
- Stakeholder dashboard live from week 5
Weeks 8–18
Execution & Governance
Migrations executed wave by wave with real-time monitoring. Every identity movement tracked in ACQI's governance layer. Synergy tracking ran in parallel with integration milestones.
Outputs
- All 6 waves completed on schedule
- 99.7% cutover success rate across all users
- Zero P1 incidents during migration windows
- Full audit trail captured for compliance review
- Synergy tracker showed £2.1M in identified IT savings
ACQI modules deployed
Six module categories ran concurrently across all four tenant environments.
Azure Discovery
CloudScanned all 4 Azure subscriptions: VMs, networking, storage, databases, serverless, and access policies.
Active Directory
IdentityMapped 3 AD forests, all OUs, group policies, trusts, and 47K+ user and computer objects.
M365 Deep Dive
ProductivityExchange, SharePoint, Teams, OneDrive — full data footprint with licence utilisation and collaboration graphs.
Identity & Access
SecurityEntra ID, conditional access, PIM assignments, managed identities, service principals across all tenants.
Application Discovery
AppsInstalled applications, SaaS subscriptions, licensing counts, and application-to-identity dependency mapping.
Intune / Endpoint
DevicesDevice compliance, enrolment status, configuration profiles, and autopilot deployment rings.
Results
Eighteen weeks. Four tenants merged. No P1 incidents. The integration was delivered on the original board-mandated deadline — something the team attributed directly to having complete discovery data before the first migration window was booked.
On time. On budget.
The 18-week deadline was met without scope reduction or weekend emergency cutovers. The discovery phase eliminated the usual "discovery during migration" pattern that accounts for most M&A IT overruns.
£2.1M in identified IT synergies
ACQI's governance layer tracked synergy realisation in parallel with the migration. Duplicate SaaS licences, redundant infrastructure, and consolidated vendor contracts were identified automatically from discovery data.
What made the difference
Most multi-tenant consolidations overrun because teams are doing discovery and migration at the same time. An undocumented legacy system surfaces during a migration window. A conditional access policy conflict breaks authentication for a critical application. An AD trust with an undocumented service account dependency causes a production outage at 3am.
This team avoided all of that. ACQI ran 124 discovery modules across all four environments in the first three weeks. Every identity, every application, every policy, every dependency was catalogued and cross-referenced before a single migration window was booked. The migration team had complete information. The Go/No-Go gates had something to gate against. The rollback procedures were written for actual known dependencies — not guessed ones.
Discovery is not optional in M&A integration. It is the work. Everything that follows is just executing against a known state.
Running a consolidation right now?
The fastest path to a successful multi-tenant consolidation is knowing exactly what you're consolidating. ACQI has the modules. Start scanning on Day 1.
Related capabilities
Multi-Cloud Discovery
124 modules scanning Azure, AWS, M365, and on-prem in parallel
Identity Consolidation
AD forests, Entra ID tenants, conditional access, PIM — fully mapped
Wave-Based Migration
Dependency-ordered migration planning with Go/No-Go enforcement
Synergy Governance
Licence rationalisation and IT synergy tracking from Day 1