Hi all, really confusing situation here. I booked a return from HND <> LHR recently on the BA website, both legs flown by JAL. I am a JAL crystal + platinum card holder and have enrolled in tour premium. I've used this site to calculate my FOP and for my HND > LHR flight I got the correct 2892/1866 miles/FOP (i.e. this was a 30% fare). However for the return flight I got 4821/3510 miles/FOP. This is in correspondence to the 50% fare, but without the tour premium enrollment. It should have been 7931/3510 (i.e. more miles). I see that the HND > LHR flight was posted as JL44, but the leg out was posted as BA4603. Is this why I didn't get the extra miles? And if so, why was it posted as this and not the JAL number, given that both flights were on the same reservation and both flown by JAL?

Thanks!