Actually I exaggerated a bit with that 'years away'. IOC for the A seems likely in 2016, between August and September. And here's the definition.
Air Force F-35A initial operational capability (IOC) shall be declared when the first operational squadron is equipped with 12-24 aircraft, and Airmen are trained, manned, and equipped to conduct basic Close Air Support (CAS), Interdiction, and limited Suppression and Destruction of Enemy Air Defense (SEAD/DEAD) operations in a contested environment. Based on the current F-35 Joint Program Office (JPO) schedule, the F-35A will reach the IOC milestone between August 2016 (Objective) and December 2016 (Threshold). Should capability delivery experience changes or delays, this estimate will be revised appropriately.
https://www.f35.com/news/detail/depa...-all-services/
That was in 2013 - but they seem to be sticking with it.
airsound