Not in Biab but this is one of the great features of Real Band. RB is not sinply another version of Biab, it's it's own discrete 48 track audio/midi sequencing program but it opens Biab files, generates Biab tracks either midi or Real Tracks/Drums and does it on a track by track or bar by bar basis using different styles if you want. Check it out.
If you want to stay in Biab anyway, the workaround is to use two tracks for the bass and use the "mute bars" function so your original bass track stays as is but you mute the 8 or 12 bar section you don't like and then using another instrument track that's not part of the style like maybe the strings, melody or solo track create another bass RT but mute everything but that same 8 to 12 bar section. Once it's given you the two parts you like, freeze the tracks.
The big difference between this and using RB is Biab can only use one style at a time but you can change styles during the song but RB can use different styles anywhere you want on any track or any part of a track without changing what you've already generated. That opens up a ton of possibilities.

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.