Our Approval Path goes: User submits, Supervisor Approved and HR makes final Approval.
System allows users to book time off in an approved timesheet when the supervisor has approved but HR has not yet approved. It also does not reopen the time sheet.
The system validation should prevent this behavior as it does in Gen 2.
We have two employees that got paid extra because they booked time off on an first step approved time sheet. I have been over the Audit logs with support and confirmed this problematic behavior that did not exist in Gen 2.