Rednacks

Hi everyone,

My question is quite simple although the situation is complicated.
I am currently BA Executive Silver and plan to take the Delta SkyMiles challenge to become Delta Medallion Gold for 3 months.
However my main FFP is Flying Blue and I usually fly Air France, I am just leveraging my BA Executive Silver status to get a status matching with a Skyteam member FFP to access AF lounges at CDG.

My question is the following: I know I am eligible to AF lounges at CDG if I become Delta Medallion Gold, but what if I register my Flying Blue number (to still gain miles on AFKL FB) on my booking and show my Delta Gold card at the lounge .. ?

Thanks.