In a style, you may have drums patterns for bar#1, bar#2, bar#3 and bar#4 (up to bar#8).
If you place a part marker at bar#5 for example, you expect to get a fill bar at bar#4.
In this case, BIAB may play the bar#4 pattern or sometimes it plays a fill bar. So, you are not sure to get a fill bar as expected.
Solution : add an option to give high priority to the fill bar against the bar#4 or bar#8 pattern.

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