Planner and SharePoint Sites

[escupham]

I understand Planner runs off the groups service and a SharePoint site is created when a plan is created.  A couple questions:

1.  Why don't Sites created off the Plans show up in the SharePoint Admin center under Site Collections?

2.  If you run the PowerShell script to disable Groups service, will that also disable then the automatic creation of a Site when a Plan is created?

[#2]

1.- Sites for Planner, as happens with Groups, are marked as hidden so that's the reason why you don't see the sites on the SPO Admin Center. You can use PowerShell to get them...by the way, this is going to change in the future.
2.- Planner requires Groups, so if you disable Groups creation you are not going to be able to create Plans properly

[#3]

Thanks.  So if we are about to disable groups, we should probably unlicense everyone for Planner?

[#4]

That's correct

[#5]

We ran the PowerShell Command,  UserPermissionToCreateGroupsEnabled parameter is set to FALSE, and confirmed users could no longer create a Plan.

I have found a couple different mentions of commands to run to disable O365 Groups service.  If we've ran the above command, do we need to run this one too before we start migrating mailboxes to EO:  set-OwaMailboxPolicy -GroupCreationEnabled $false -Identity OwaMailboxPolicy-Default?