There seems to be an issue with the altitude settings in the 787 (I havent checked other aircraft yet since the last update) and what air traffic are seeing. I have done a couple of flights since the update, cruising altitude FL 400, barometer pressure correct at 2992 or 1013, however ATC are constantly telling me to get to correct altitide of FL400, when i am already at it.
I have tinkered around and found the other day that there can be a 300ft difference +/- although on a flight right now i have been told that i am 700ft below FL400, when all my instruments and barometric pressure are telling me I am golden.
This is a bug since the most recent update.