The 1982-2019 dates are the right ones, in my view anyway. There are only 2 “start” dates that will count for much in the historical record: the first flight in 1974 and the declaration of operational squadron service in 1982. Everything in between, including first production deliveries and formation of training units, are dates that may mean a lot to those who were there but hold no particular significance beyond being milestones on the way to a capability. You can see that today with the F35 Force; who knows or cares when our pilots started to be trained? The recent declaration of IOC marks the start date for that as a fighting outfit.
1982 it is!