EPC Group Unveils Plan for October 2026 Microsoft Deadline Triad

EPC Group, a Houston-based Microsoft consulting firm, has released a three-week triage plan to help organizations prepare for a critical deadline on October 13, 2026. On this date, three major Microsoft support cycles will end simultaneously: Office LTSC 2021 will reach end of support, the first year of Windows 10 Extended Security Updates (ESU) will expire, and the final year of ESU for Windows Server 2012 and 2012 R2 will conclude.

The firm's plan aims to sort every affected device into one of four paths before any license or ESU purchase is made. The first week focuses on counting and inventorying devices, the second week assigns each device to a specific path, and the third week executes the plan in deadline order. Path A involves moving users to Microsoft 365 Apps on supported Windows 11 devices, Path B covers Office LTSC 2024 for on-premises devices, Path C includes purchasing Windows 10 ESU Year 2 as a temporary solution, and Path D addresses retiring or replacing Windows Server 2012 and 2012 R2 workloads.

Errin O'Connor, Founder and Chief AI Architect of EPC Group, highlighted the risks of unsupported systems. He noted that the exposure is particularly high where Windows 10 PCs running Office LTSC 2021 interact with Windows Server 2012 file servers, creating a completely unsupported chain as of October 14, 2026.

EPC Group's plan includes checklists for each path and questions assessors may ask about devices remaining on a bridge. The firm has extensive experience in Microsoft 365 license optimization and consulting, having completed over 216 merger-and-acquisition tenant migrations covering 1.83 million users since 1997.