The APs will work fine never being connected to any Hivemanager (on-premise or HMOL) as long as you can configure them from their console connection or via SSH.
If it is ever connected to a Hivemanager, you can configure it and when you are done, it never has to connect again and be fine.
I had an old customer that configured APs via a remote 1U HM but just used the APs for a local WLAN that had no internet access (in another country). And they worked flawlessly for their needs.
One note however is if you configure them and the configuration causes them to lose connection, they have a rollback timer that will revert their configuration back to what it was prior to the most recent configuration update. So I always recommended that the customer push out configs and let the AP reconnect back to their HM instance. Then they were able to disconnect them and use them as they pleased.