There would most assuredly be a common syllabi for the A and B, you then just add the element of STOVL trg for those destined for the B. Remember the Mission Systems of F-35 family are 99% the same. The selection of the A over the C would actually save on the requirement to train, because there is no additional burden to train cats and traps which is a massive overhead (FCLP etc)
Sorry but the whole orphan paranoia is exactly that, paranoia. The F-35B fleet will be very difficult to cull while there are Carriers. What else would replace them? Let's not clutch at straws.