Configured domain pair (source / target).
Host name resolution verified, (can ping short names).
Netdom with /enablesidhistory:yes was run.
Source users already exist in target AD, (different UPN and samaccountnames), have O365 licenses and O365/Exchange Online mailboxes, (long story).
Use QMM to migrate the security groups.
Configure Dir Sync by OU, skip UPN, samaccountname and pwds? Dir Sync not required if co-existence isn't needed?
Configure RUM PC and Server collections. Run Discovery.
I've migrated Exchange mailbox data up to 2 months ago using ODME. Will complete the remaining data on cutover weekend.
Start Resource Update Process from RUM collections to create profiles on target PCs & servers.
Migrate users. Enable target accts, disable source accts.
Perform domain moves for PCs & servers.
Migrate mailboxes from 2 months ago to current date. This last one will include modifying the Outlook profile.
Remove RUM agent service.
Active Directory Processing Wizard, update memberships/permissions.
Exchange Processing Wizard. Does this work after migrating to O365 and decommissioning the on-prem Exchange servers?