What I'm saying is there is no reason I can see that the method I describe can't be integrated into Biab now, like today, if I had the source code I would code it now and upload it.
Whatever the first time signature is set to it will play 2 bars of that then start play at bar 1 or a custom start point.
Maybe it's because they spend 6 months re-programming Mac that there is not the time left to fit these things in, I don't know......

Watch https://www.dropbox.com/s/nf3htbh420pkbx6/Reaper-Count-In.mp4?dl=0