I'm not worried about 801 vanishing. It disappearred from 1970 to 1981 last time and came back when it was needed. I expect those NSW personnell who wear 801 badges instead of 800 currently will probably continue to do so... 800 NAS also disappeared from 1972 to 1980 and returned ready for action! In 1979 the FAA had no FJ frontline sqns at all and just one second line sqn (700A) and nobody believed the FAA would die out then!
My point is, last time around when the SHAR FRS1 entered service, it did not re equip existing sqns, old ones were reformed as required, and I believe the same will happen with F-35.