Depends what your code does.

Evidently you can't switch while it's executed, but if you have the possibility to safely freeze, you could eval the code into an alternate namespace, and call the "main routine" there. (don't forget to empty the module before populating it)

You would flip-flop from Module_a to Module_b for each release.

Frozen data should be put into Module_Data.

Like this you wouldn't need to stop and start a process.

HTH!