We are doing a night before at LAX (have to make less-than-optimal connections). Just want to spend more time in the CDG lounge and not get in so early at BKK (0700!). FWIW, not only did the ticket number not change but AF and QR annoyingly both use the same PNR as SV. I'll keep an eye on inventory in case the 1st flight starts to fill up (cheap BC seats appear to be disappearing for the earlier flight).