Cannot initiate Dual-boot in latest firmware

Following this:

The long press power in Android, brings up a menu and Ubuntu option is there. - This works.

The ‘function’ button I cannot get to operate.

Actually, I still would prefer that it would default the other way around - IE: always Ubuntu, with Android as the option.

Or even better - Always boot to what I selected, until I change it and then alway boot that.

I dont want to be holding buttons in and facing North every time I want Ubuntu, and stand on my head facing East for Android!