Alright thanks I will check it out.
I was not thinking of something like editing the tags, because it's not very 'dynamic'. I remembered this functionality from an old MP3 player I had and I could just go to a point, give it an A, go to the next, give it B and it would repeat. If I wanted to select a different part, erase, new A, new B. This is what I mean by dynamic. Since I know nothing about the 2 other points I'll investigate on those, certainly.
Thanks a lot for the tip!