Split upgrade priority without splitting PNR
 

TLDR: Checking in at airport splits priority in a PNR, while OLCI drags entire PNR to priority of lowest status member.

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This weekend:

PNR 1: a DM + GM, check in at the airport via agent at T-1.5.
PNR 2: a DM + GM, OLCI at T-24.

For both PNR's, all other factors were identical, with the one exception that PNR 1 was booked 30 seconds earlier than PNR2.

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PNR2, 20 some hours after initial OLCI, was something like 9th and 10th out of 14 for 3 seats .

PNR1, after checking in at the airport (no special instructions, just normal check in), took 1st and 10th positions out of 16, pushing PNR2 to 11th and 12th out of 16.

This was unexpected. So without splitting PNRs, checking in directly at the airport led to a split in priority. While OLCI dragged both members of the PNR to the lower priority as expected.

Why not just split it over the phone before the upgrade windows (until they finally implement the new policy)