Hi, due to a merger, I need to fully decommission our current O365/Exchange full hybrid implementation.
All Exchange related stuff should be moved out of the Azure tenant and back to on-premise, and the email domains need to be de-coupled from the O365 tenant, and all hybrid settings should be removed from Exchange and AD.
After the decommission, the mailboxes will be migrated (cutover migration) into the O365 tenant of the new parent company. (obviousy, that's a different tenant than the one we're curently using)
I understand that any mailboxes in O365 have to be moved on-premise again, and mail routing and autodiscover should pass via the on-premise Exchange. (this is still the case anyway)
What I don't know: how to properly decommission / uninstall / remove all the settings that have been set by the HCW (Hybrid Configuration Wizard), both in Exchange Online, and on-premise Exchange and AD. There is no uninstall option in the HCW.
Any guidance or reference links ?