generate different durations of track generated in genate music

I’ve been using the AI music generation feature. 

What I’m finding is that sometimes my edit changes and I want a longer version of a track. There is currently no way to do this except within Premiere itself where it uses AI to adjust the duration but this feels not ideal. You can put the same prompt and a longer duration into Firefly, but you will get different tracks. It would be great if once you manage to generate a piece of AI music that works, you could get iterations of it. This could include duration as well as stems (give me just the drums, or just the guitar etc).