Hi Sam

The ability to suspend or delete a site administrator has been disabled to prevent the only active Site Admin being locked out of the system and no one able to perform site admin functions.

I can't see a way around this apart from using the HR Import as you can't login as a site admin and can't access the account to make it a non site admin.

What would be needed is  before the site admin user is suspended  they need to be unassigned as a Site admin

Hopefully someone else may have a workaround

regards