I have a handful of V2 cameras at various versions of the beta firmware. Is it possible to force the ones on back versions to upgrade?
yes, you can manually rollback/update v2 firmware, please use the below link for reference.
Before trying to flash the firmware, did you Check for Update in the Device Info section of the camera settings page in the app?
Yes, there’s no button to update there.
If you are also running the latest beta version of the app, then I would follow the link that HDRay provided above.