Originally Posted by
IAN-UK
That solution appeals to my inner geek, but can give a false sense of security. Finnair's system may not accept all, or indeed any, of the allocations made through third parties. When i called Finnair the seat hadn't made it over to AY from MH, although they did show up on BAEC's MMB. I have a feeling Finnair's IT could give BA's a run for its money in terms of crankiness.
Calling or web chatting Finnair to make the seat allocation seems the best way of handling it: it's simple enough if you have the patience to wait or to fight the chatbot for human attention
I have tweeted them to do seat selection before which has worked at FinnairHelps
Tbh I often check on EF to see whether the seat selection has stuck after changing on RJ or RAM, and it has usually been fine, I have done it this way for a few years when booking AY on BA codes and I haven't had one where it hasn't been fine on the flight. I haven't tried MH before.