My theory is that the reprogramming does not play well with a worn/weak pump.
After the dealer did the recall fix to my 2014 Sierra, the loss of braking actually got worse. It is worse to the point of instead of losing braking every so often that now it is consistent. Now when moving at slow speeds and hitting the brakes, letting off, and then hitting them again, I lose all assist and in fact the ABS kicks on even at 5 mph.
At least no more surprised loss of braking, it's all the time now!
Truck is once again sitting in the dealership. Already waiting for parts for ball joints and steering gears (all covered under extended warranty) because of the strike. Looks like now it might be waiting for a pump, but don't know as they have not called me back yet.
Gawd am I thankful I still have my old 1997 Silverado.