Sorry to hear that Changeup. Both of my grandfathers were in the RCAF, with one being in the RAF with the Canadians right from before the BoB onwards. The other grandfather flew in Lancasters. I wish they both would have lived long enough to see this game, as one of them introduced me to flight simulators WAY back on the C64 and early PC's. I know they would have both been truly impressed as well.
I had no idea about the story of the B25, that skin, and your grandfather Changeup, it's incredible what you can miss on this bbs. I'll always think of this story now whenever I see or fly B25's, so your ancestors will never be forgotten in that way.