Hypercare Support for M365 Tenant-to-tenant Migration

We are seeking an experienced Microsoft 365 engineer to provide hypercare support during and immediately after tenant migration cutovers. These will be short-term, high-intensity engagements focused on the go-live window and the stabilization period that follows. You will be the front line for triaging and resolving end-user and mail-flow issues as users transition to the target tenant, so calm troubleshooting under pressure and strong communication matter as much as technical depth. This is not a project-planning or migration-architecture role. The cutover design and tooling will already be in place. Your job is to keep users productive and resolve issues fast during the critical hours and days around each cutover. What you'll do: Provide real-time support during scheduled cutover windows (some evenings and weekends expected) Validate mail flow, autodiscover, free/busy, and coexistence teardown post-cutover Troubleshoot Outlook profile rebuilds, OWA, and mobile (Outlook mobile, native iOS/Android) re-provisioning Resolve Teams sign-in, chat/history, and channel access issues after migration Support OneDrive and SharePoint re-sync, known-folder-move, and permissions issues Assist users through MFA re-registration and Conditional Access prompts in the target tenant Handle identity edge cases: sign-in failures, licensing, delegate/shared mailbox access, distribution list and resource mailbox behavior Document recurring issues and feed patterns back to the migration lead for batch remediation Escalate cleanly with clear reproduction steps when an issue is beyond hypercare scope Required skills and experience: Hands-on M365 tenant-to-tenant or on-prem-to-cloud migration support, ideally in a cutover or hypercare capacity Strong Exchange Online administration: mail flow, transport rules, DNS/MX/autodiscover, hybrid coexistence concepts Working knowledge of Entra ID (Azure AD): users, licensing, MFA, Conditional Access, sign-in log analysis Teams, OneDrive, and SharePoint Online end-user troubleshooting Comfort with the M365 admin centers and PowerShell (Exchange Online, Microsoft Graph) for triage and bulk fixes Excellent written communication and the ability to explain fixes to non-technical users with patience Reliable availability during agreed cutover windows, including off-hours Nice to have: Experience with cross-tenant migration tooling ([e.g., Quest On Demand, BitTitan MigrationWiz, ShareGate, CloudM] adjust to match the engagement) Intune / device re-enrollment experience Prior work supporting mid-to-large enterprise environments Familiarity with ticketing and rapid triage workflows