I had something similar happen just after buying iniBuilds KLAX on a flight from there to KSFO. I landed and all of the buildings were gone. After some searching I found a post somewhere that having high FSLTL settings can cause this in combination with GSX and large/busy airports because it exceeds the number of “sim objects” it can render. In my case I had FSLTL settings really high (I think like 90+ for IFR aircraft) and lowered it to 50 and haven’t seen the problem since.
At the time I was not running the Oct. 5 version of GSX. If you’re not using FSLTL then might be a different issue but I haven’t seen it again and now I’m on latest GSX and still using FSLTL but with lower settings.