When you turn off weekends in the gantt view, it turns them off in day scale but not in the week scale
This happens to me too, this gantt is so buggy, when you go out from that view and enter again the tasks get rescheduled, and the tasks move around way too much!, this feature is nice, but doesn't work well, I've tried enabling auto save layout without luck it always distortions the tasks in weekends
Hey Ivan! Good find! Thanks for the report.