Crediting Delta Flights
First, I'm not sure if this belongs here or in the Delta forum, so sorry if it's in the wrong place.
I have Flying Blue that will expire soon so I'm planning to take a short flight to keep them alive. It looks like I can do this by crediting a Delta flight, so that's nice. I have platinum status with SkyMiles so if I book through my account I can get a "Comfort+" "upgrade" immediately and I think I can change the FF number to my Flying Blue account after. But if I do this, the booking class shows as SU and I'm concerned this would affect the miles crediting to FB. I can't find an answer to this exact question here but from what I've read FB will use the underlying fare class and it shouldn't post a problem.
Do any of you wise forum sages know if this will be a problem or if I'm just being paranoid? Thanks in advance.