Idea for a future.
How about recognizing partial commands by the minimal unabigous chunk?, like some software does (lldb being my favorite example)
duplicacy b can only mean backup, so no reason to force user to spell it out.
Same with other arguments, including -la (or even -l for last or latest), for example,
duplicacy l -r l -f is unambiguous and quick to type.
It may sound ridiculous but for frequent users it’s a massive time saver.
One might argue that unlike lldb nobody is going to use duplicacy manually daily so that is not a problem — and I would totally agree. I just thought about this approach in the light of discussion of whether latest or last is better — why not take it to the extreme ?