No ferry range figure was ever published for any F-35 variant. What has been published is various range requirements by plane’s users, USAF, USN and so on. What they state is that the plane has X range while carrying Y set of weaponry on a very specific altitude path at specific speeds with a very specific excess fuel reserved for maneuvering. Of course, all these specifics are classified. What we do know is that a strike mission USAF needs allows F35A to cover 600 nm. In pure air to air mission, the same F35A can cover 750 nm.

All that suggests F-35A has potential ferry range of some 1600 nm, possibly even 1700nm.