Dear,
I think the problem is in your rescheduling horizon.
Rescheduling horizon is calculated after starting at the end of the RLT (replenishment lead time).
End of RLT = Planning Date + number of days for RLT.
The first case comes inside the Rescheduling horizon, while the second does not. Please test once increasing the Rescheduling horizon to a larger value (say 60) and check.
Best Regards,
Rajen