Thanks for all your help here.

I've noticed that the tempo is frozen (as in doesn't change when I change style) on some of my recent projects too, and it just froze in a new test project but I can't seem to reproduce it by following the same steps again.

I suspect it's either a bug or a feature that I just haven't got my head around. I couldn't find anything in the help file about it.

I may raise it with support to try and clarify. I'm hoping my projects aren't corrupt for some reason.

It's a shame if it is a bug because I find it very useful. The first thing I do when writing a song is work out the right tempo, so whenever I audition a different style I have to remember to set the tempo back to what it was, even if it's a small change it can still mess me up, especially if I've already copied some instruments to my DAW.