Of course, the F-35Bs delivered so far have been for the RAF, not the Navy
So are not yet cleared for seaboard operations. And then there's the way the US defines 'seaboard' as within 200 miles of the sea. And then there's the fact that it's impossible to get 200 miles from the sea in the UK. Don't worry, I'm sure someone's planned it all out. The Merlin worked out perfectly, after all...