Prior Reservation Flag is not honored by Generate Shipment Request

Summary:

Hi Team,

1. Created SO with 2 lines
2. Hard Reserve one of the Lines
3. Perform Create Pick Wave with "Prior Reservation Checkbox" checked OR Execute ESS: Schedule Pick Wave ESS job with Pick wave release rule having "Prior Reservation Checkbox" checked
4. Only 1 line gets processed as expected. 

1. Create SO with 2 lines
2. Hard Reserve one of the Lines
3. Execute Generate Shipment Request with Pick wave Release Rule (Also in the release rule we have "Prior Reservation Checkbox" checked) 
4. For both the lines, the Integration status changes from Ready to Interfaced to Interfaced.

QUESTION/Query: Shouldn't only one line get picked by the Generate Shipment Request, since only one line is hard reserved.