I havent had issues with mine, and regularly get a good +/- 3m accuracy in lightly forested areas. Sometimes accuracy drops, but most of the time it isnt bad.
My guess is they will let some go that are not "mission critical", and keep up the ones they need. Eventually, they will be replaced....our whole military runs on them now, and Garmin, as well as other manufacturers, would likely sue the government if it were allowed to deteriorate too far.