I agree with MusicStudent - they are midi styles that support more than just an A and a B substyle. It might be an instrument change, or a change in pattern, but I don't think it was much more than that. I think the intent was to have a different "feel" for the intro, A, B, and bridge sections.

I believe you can build multi-styles with the Style Builder, perhaps with more than 4 substyles (but I haven't tried it). You can identify RT in a style with the style builder, so you could perhaps build a Real Style with different RTs.


BIAB for Windows Version 2019 (643)
Windows 10 (1909)