How best to add every team in your tenant to the Office 365 Groups Expiration Policy? Well, one way is to check all groups for Teams. Another is to use Get-Team to return the set of teams and process those. But then you should think about how to mark the teams that are in the policy in such a way that you don’t process them again. It’s easy to do this with one of the Exchange Online custom attributes.
Like all mail-enabled objects, Office 365 Groups can have multiple proxy addresses. Microsoft has fixed a bug in the Set-UnifiedGroup cmdlet so that you can remove proxy addresses from groups, but take care before you do.