MRP Messages are not generating when demand date is same as PO Schedule pick

We notice that when an item's demand date is same as PO schedule pick (F4311.PDDJ) then MRP gen (R3483) is not generating any message.

If demand date is less than PO schedule pick then we get "Deferred" message.

If demand date is more than PO schedule pick then we get "Expedite" message.

Is this expected functionality or are we missing a setup?

Below is an example for more context:

Step 1: Ran R3483 full regeneration. Created a new message

Step 2: Created a PO from the message

Step 3: Ran R3483 full regeneration. NO message generated

Step 4: Change the PO schedule pick date from 23-Sep to 2