If you need to get an employee out of Office 365 immediately, here are the recommended steps from Protected Trust
- Block the users sign-in and reset their password.
- Sign the user out of all Office 365 apps and sessions immediately.
- Convert user to a shared mailbox; give full access to mailbox if someone needs to access the data.
- Wipe and block user's mobile device to remove business data from the phone or tablet.
- Move the user's OneDrive content.
- If they used a personal computer instead of a company-issued computer to download files from OneDrive and SharePoint, there's no way for you to wipe those files they stored. They will continue to have access to any files that were synced to their computer.
- Remove the license from the user and contact Protected Trust and request to remove the license from billing.
Do not remove the license if the account has online archiving.