Thank you, I appreciate your reply, however I don't quite understand and hope you can explain a bit further.
There are 5 differently colored discard slots, A B C D E. Right now if I discard to, let's say slot B, I am then able to pick my new card from slots A C D E or the draw pile. I'm asking to be able to pick my new card from slots A B C D E or the draw pile. So, the request is for removal of the feature which locks slot B, rather than adding a new function. I hope this helps. I guess I think of the existing lock as more complexity: an added feature that didn't need to be there (and of course that's easy for me to say, not having done the programming lol).
It's possible that you lock slot B as a safety to prevent errant movement from accidentally repicking the card just placed, I don't know.
Again thank you for consideration and reply.