You don't have to keep a 20-L on the programming port for "normal" operation, only for programming. So, move your programming port to #02, keep #01 as your operator with the 20-L. When you need to program, unplug the 20-L from its jack and move it to the programming extension, do your programming, then put it back when you're done.
Or, use WinSPM for all your programming, and move the programming port to a non-20-L extension.