The unit: Spirit GT with 3.7
The goal: to have automatic rescue at a certain altitude (on a 2 level switch) and a Bailout (Acro Normal) on a momentary switch.
Spektrum DX9
I saw the option that you can have 2 banks, but that means that i have to switch banks if i want to bailout. And then I will be too late....

Is there anyone who knows how to do this?

Away at work so going from memory here but...

On Stabi page select Rescue by channel.
Then on the Channel page select the desired rescues each on it own channel and switch ie Aux 1 and Aux 2
Then in the Tx sett up the Switches to a channel ie..Aux1 and Aux 2
Confirm signal is being properly sent in the Channel page.

I know this is very general but should help you get there.