A quick reboot, rather than a complete power cycle, should suffice. The only thing that has worked for me is to turn off the base till, wait about 20 seconds, and then turn it back on. If the base unit is in a remote place, it will be difficult. I'm not sure why Arlo has such tight firmware upgrading policies.

Manually Firmware Update:

Install & launch the Arlo app or log in to my.arlo.com.
GO to Settings > My Devices.
Select arlo camera that you want to update.
Choose to click Device Info > Firmware > Update. ...
Wait for the firmwareto complete.

For more info related to arlo firmware update visit https://arlofirmwareupdate.com/