i see a lot of planes with the tail number and then it say xxxx example wja833. Whats the xxxx mean?
Had to go look at a couple flights to remember, but that is where the acft type should be. For some reason, that flight isn’t reporting the type or it’s not being interpreted. If you look at flightaware.com/live/flight/UPS2960 you can see what should be there.
Oh good call thanks for that it was really on my mind. 
XXXX appears as the type on the map (and only on the map) when the departure message doesn’t include the type. This usually only happens with flights from Canada.