There was no "ceiling" before. The game simply stopped processing air densities and whatnot at 50,000 feet. Above that was simply "more of the same" and all TAS and other computations stopped. The aircraft really can't get that high without wind assist, but they CAN get that high, and it was a glaring flaw in the game engine. I'm glad they put enough thought into it to extend it way up to 100,000 feet. Mind you, nothing could go up that high, really.
Now that the atmosphere extends higher, is there a point when your plane is just stressed beyond use and explodes, now? Something where TAS is way high and IAS is well below stall, or something?