Reverse Partial Receipt

My understanding was that receipts cannot be partially reversed.  The proper process is to reverse the entire receipt, then re-receive the proper amount.

I just had a situation where a user wanted to partially reverse a receipt.  The catch was that the original receipt had been partially vouchered.

Original Receipt was for 11 pieces, when the user made the request, 6 of the 11 had not yet been vouchered.

Using P43214, I attempted the reversal.  To my surprise, the reversal of  6 pieces was successful, without any input as to the quantity (just the verification that I wanted to reverse).

The F43214 does not have a Match Type 4 record.  The Match Type 1 record was updated.