A word to describe a new item added a completed sequence

Solution 1:

It used to be the case that, a software or game that is "complete" is Gold Edition, and should the developers find stuff they want to fix or implement later on they usually bundle all of them together and call it a Platinum Edition. These days though, those words have almost lost their meaning.

Of course, you could have already called your software "XYZ Final Edition", then all you need to do is to call it a remaster (not a software update, a graphical or auditory update) and put a few new graphics here and there along with the software update.

If there are no graphics or audio in your program or you don't want to make new ones just to call it a remaster, then I'd suggest not using any word for it at all. If it's a bugfix update, call it that. If it's a feature update, call it that. If it's just an overhaul, call it a major update and give a newer version number. Just be honest with your customers "We thought this was the final version, but as time went on, technology has progressed and we wanted to keep up with the times. So, we went back and reworked our codes and ironed out bugs and-" yada yada yada. That part is up to you.

Solution 2:

I like "postultimate". For example: In music key signatures

For flats: Key is penultimate note in key signature E.G. four flats = B E A D = Ab maj

For sharps: key is the note after the last note in key signature, i.e. the postultimate, E.g. four sharps = F C G D = Emaj