The current Boeing push towards the Navy seems to involve (1) extending the SH/Growler with the aid of FMS, until the JSF is ready for prime time and (2) developing the upgrade package, which is all retrofittable to most SHs (not the early jets with the C/D front fuselage) and all Growlers.
Let's remember what the shills don't - the F-35C was not planned as an SH replacement, but as a replacement for the last C/Ds. The Navy has already put plans in place for nearly 700 SH/Growler and has 340 F-35Cs on the books, so the type will be flying well into the 2030s, and its OSD depends on plans that haven't been formulated.
Consequently (argues Boeing) it makes sense to upgrade the jet. CFTs are very nice for the Growler, and the claims are that an engine upgrade is self-funding because the improved engine is more durable. This does not entail scrapping the F-35C - the ASH/Growler is complementary.
Mind you, if the C flunks its carrier tests next year, all bets are off again, and I suspect that Boeing and the Navy's Rhino/Growler mafia are lighting candles in church and sacrificing goats to Cthulhu in hopes that it will do so.
LW - The C is 5500 lb heavier (OEW) than the A, even without an internal gun, and with its monster wing its acceleration is much slower than the A. Jointness my
.