Why don't you export the file as audio - for whatever purpose you need and leave the BIAB track where it is and just mute it? Then unmute and do whatever you want. No need to reimport.

Unless you work on the audio track outside of BIAB in a DAW and want the edited file back in BIAB to do something with. . If that's the case use RB and then you can regenerate the BIAB track when you want. Or did you want to do something differfent?