Redeye has it correct, in order to get passover pay you have to bid the seat. If I recall correctly in the last bid after all was said and done there were openings in all FO seats except the 777.
Quite a few new hires have gone to the right seat in PANC already. I'm pretty sure no one is getting passover pay for this.
All you 727/757 FOs stop your drolling.