Contracted — countersigned (EPC-reported; documents private)First-pass editionA defense technology company (client not named) · 2026 · Project ID EPC-2026-ANON-DEF-GCCHT2T

Last updated October 25, 2026 by Errin O'Connor, Founder & Chief AI Architect, EPC Group

Opening answer. In September 2026 a defense technology company digitally countersigned a statement of work with EPC Group. The work: consolidate two source Microsoft 365 GCC High tenants into one destination GCC High tenant following an acquisition, for a baseline of up to 300 users. The production migration covers Exchange Online, SharePoint Online, OneDrive for Business and in-scope Power Automate workflows. It runs in phases over about eleven weeks: readiness and a pilot, critical-user waves, remaining waves, then close-out with evidence and stabilization. Parallel workstreams cover:

the first stage of a file-services move
permission and identity-mapping re-architecture
a hybrid identity exit roadmap
endpoint, Intune, Defender and mobile readiness
Power Automate remediation
governance readiness validation

Everyone who touches the client's GCC High data is a U.S. person working under EPC Group's direction and access controls.

Disclosure. This is an EPC-reported anonymized engagement summary. The client is not named. The countersigned statement of work is retained privately and is not published in the Evidence Center, so this account is outside the Evidence Center's documented-engagement counts. Every engagement fact below is taken from that document.

Verification class

Contracted — countersigned (EPC-reported; documents private). The client signed version 3.0 of the statement of work digitally in September 2026. Version 3.0 was revised after a final technical discovery session in August. The work is recent; no wave completion, acceptance or outcome measurement is cited or claimed.

Buyer problem and scope

Item	What the statement of work states
Buyer	A defense technology company (client not named)
Situation	Two source GCC High tenants after an acquisition, to be consolidated into one destination GCC High tenant
Baseline	Up to 300 users
Production migration	Exchange Online, SharePoint Online, OneDrive for Business and in-scope Power Automate workflows. Teams chat, channel and file migration excluded
Phase 1 (weeks 1–2)	Readiness, inventory, identity validation and a representative pilot
Phase 2 (weeks 3–6)	Critical-user production waves
Phase 3 (weeks 7–9)	Remaining user waves
Phase 4 (weeks 10–11)	Close-out, compliance evidence, stabilization and formal hand-off
Workstreams	File services stage 1 for a DFS-replicated environment of a few terabytes (discovery, classification, Azure landing target, permissions, access validation, cut-over planning); permission, group and identity-mapping re-architecture (naming conventions, group taxonomy, UPN collisions); a hybrid identity exit roadmap; endpoint architecture, pilot and Intune/Defender validation with a transition runbook; mobile and BYOD app-protection discovery and pilot; Power Automate remediation for workflows that point to changing SharePoint URLs; migration-impact review of destination governance controls
Explicit follow-on work (excluded)	Full Purview classification, CUI tagging, DLP redesign and Copilot governance implementation; report redevelopment or Fabric work; full hands-on migration of every device
Governance	Lead-architect accountability for go/no-go and rollback decisions; named backup coverage; a licensing and entitlement readiness gate; acceptance and deemed-acceptance terms

Unknowns, not stated in the document cited: mailbox and content volumes, wave dates and any measured result.

Approach and artifacts

Re-scope honestly after discovery. Version 3.0 sets out what changed after the final technical discovery session. Each item that was not in the original workload list is shown with its new treatment:

file services
permission re-architecture
workflows that point to SharePoint URLs that will change
endpoint and mobile transition
downstream report dependencies

The client reviews the complete plan before signing.

Pilot, then waves, with a way back. A representative pilot comes before any production wave. Critical users move first, and rollback authority sits with the lead architect.

Draw the line around compliance work. The migration includes a migration-impact review and readiness validation of the destination's governance controls. Purview classification, CUI tagging, DLP redesign and Copilot governance are named as follow-on work, so the migration scope stays clear.

Document (held privately):

Document	Date
Statement of work, GCC High tenant-to-tenant migration, version 3.0 (digitally countersigned)	September 2026

Results and limitations

Claim	Basis	Status
The company contracted EPC Group to consolidate two GCC High tenants into one	Countersigned statement of work, September 2026	Contracted (EPC-reported; documents private)
Waves completed, cut-over done, or measured results	No document cited	Not claimed

Provenance

Source: the countersigned statement of work (September 2026), held privately. Engagement ID: EPC-2026-ANON-DEF-GCCHT2T, an alias unrelated to the client's name.
Anonymization: industry only, under EPC Group's anonymized-case rule; the company's name, the acquired company, programs, location, staff names and commercial terms are not published.
Not claimed: client endorsement, completion, or any measured result.
Author: Errin O'Connor, Founder & Chief AI Architect, EPC Group, named in the statement of work as lead architect and executive sponsor.

Revision history

2026-10-25: anonymized engagement summary published from the engagement's countersigned statement of work.

Author: Errin O'Connor, Founder & Chief AI Architect, EPC Group · Published: 2026-10-25.

Anonymized engagement summary: consolidating two Microsoft 365 GCC High tenants into one after an acquisition, for a defense technology company (2026)