Can you imagine the day when it is still flying and there isn't anyone who was alive on the day they first took flight?
There are already cases of pilots flying the same aircraft, by tail number than their grandfather had flown. :) But not really the same airplane. New avionics a couple of times, not counting all the different EW fits. They've removed the tail gun. (Only took 20-30 years or so, but they just about had it approved, when some sergeant shot down a MiG over North Vietnam. :) But it made me sick to see a BUFF in a maintenance hanger at Tinker about 10 years ago, with no tail gun, just a rather ugly fairing. They haven't scrapped the guns, nor done anything to preclude remounting them, AFAIK.