I can't imagine that the programmers would allow MIDI channel 2 input then.
Then they would have to point out that for the utility tracks you may only take the MIDI channels from 11.
The management of the channels must be done internally in the BIAB.
The MIDI tracks already contain events with different channels, if you use the list editor you can see that. Someone of the developers should explain the MIDI event and channel management. So what has priority and how that is managed internally. (especially volume, program change and channel)

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