Our new upgrade/downgrade policy means that once users upgrade their FCV, they will not be able to do a binary downgrade without the help of the support team. This could cause a lot of distress for customers who won't realize that they cannot downgrade on their own until it's too late.

The setFCV command will now require an extra parameter

to do an FCV upgrade/downgrade. Without that parameter, the setFCV downgrade command will error and say that an FCV + binary downgrade will require support assistance, and to re-run the setFCV downgrade command with the confirm parameter if you acknowledge that. The setFCV upgrade command will error and say that once you have upgraded to <targetFCV>, FCV + binary downgrade will not be possible without support assistance, and to re-run the setFCV upgrade command with the confirm parameter if you acknowledge that risk.