Is there a rule of thumb as far as how many seats JAL opens to AS in J when AS shows availability or is it a total crapshoot? Looking to upgrade a couple Y tickets to J (AS currently shows availability), but I'm currently waiting on some Bonvoy points to transfer over to AS to complete the upgrade and wondering what my odds are that the J seats will get snatched before then. JAL shows a healthy amount of cash fare availability in the cabin for the same flight FWIW.