As you may know Office 365 admin center doesn’t provide the capability to remove/delete deleted user from recycle bin and you may need to run powershell to do it.
Some of the IT admins may find using power shell is not very efficient than GUI. Currently you could perform the remove at Azure active directory.
- Sign in to https://portal.azure.com
- At the side bar, select “Azure Active Directory”
4. Than select “Users”
5. Select “Deleted Users”
6. Next, select the users that you wish to permanently remove
Yes, Microsoft default of permanent remove of deleted user’s account is after 30 days.