Just take a snapshot of your VM after you have configured it the way you like. I do this with VMWare. When 90 days goes by, roll back to that snap shot. take

Just take a snapshot of your VM after you have configured it the way you like. I do this with VMWare. When 90 days goes by, roll back to that snap shot. take note of anything you upgraded since so you can create a new 90 day snapshot with more of the recent updates