Time to change
As others have mentioned in this post, and as anyone who has been under an actual “donate“ situation, what gets donated is actually the primary. Few people are under Duress and stress and able to think through signing that they are out of air and would like to “borrow“ your secondary. The reality is they grab your primary out of your mouth.
You should practice this, you should train for this, you should plan for this.
In whatever situation is easiest for you, build your new set up, and practice with a buddy these different donate scenarios. It will become second nature very quickly.