Hey I had it working inconsistently for me just now and I was looking for a solution, but I couldn’t find it here (maybe this solution is already documented somewhere, but I couldn’t find it). So I just dug a little deeper into what @Brockstar said about the page parameters. I found out that the problem starts when I enable length per track. Specifically, if I put the master length on infinite on the box that needs to follow the other box, it will start changing program one bar too late. But if I put it on 16, 32 or however long the pattern actually is, it changes in time. (but of course with 32 it might be late if the 32 hasn’t completed yet). The page parameters do not need to be the same between the boxes and ch. length can be off or whatever. The only thing that seems to matter (for me) is if master length is set to infinite on the box that receives the program changes.