Yes, and I was able to select seats for all but one flight (JL inbound) through RJ. The same PNR worked on the JL website/app, however, so I was able to select a seat and meal preferences for both JL flights.

We flew with only hand luggage on the outbound but checked cases on the return as we’d bought knives in Osaka and there seemed to be no issue at HND with checking them all the way through to MAD. This meant that although we’d checked in on the app as before and generated mobile BPs, we had to have paper BPs printed out in BKK by the RJ gate agents who wanted to confirm we’d checked bags at HND.

On returning to the airport after the 27h stopover in AMM, the check in agents there had to call someone to retrieve our bags and issue a new tracking number for them saying they wouldn’t have made it to MAD otherwise (we asked and gave them the JL tracking slip given what had happened in BKK) but they were able to do this in about 10 mins and the bags made it to MAD (and then home) with us.

We were very fortunate not to have encountered any itinerary-breaking delays - and to an extent the length of the stopovers cushioned us in that regard - so I don’t know how things would have gone if we’d missed a connection as a result of a delay.

Thankfully, the last of the oTPs posted on 31/03 so it was a clean 6 x 140oTPs. On that point, RJ - on both legs - posted their TPs on the day after completing the second of their 2 flights. JL took 4 days to post the outbound (flew on Wed, posted on Sun) and 8 days to post the inbound (flew on Sat, posted the following Sun).