Yeah, X-plan is a good priced for new model vehicles (i.e. ordering the 2016 it's a solid price) but at this point most dealers should be able to beat X-plan pricing for 2015s they have in stock. The deals on 2015s will get even better in August/September when 2016s start arriving.
I bet you...
If the dealer really tries to pull a scumbaggy move like that, a move which is also against X-plan rules, then you should escalate this situation immediately to Ford. There are apparently Ford reps on this board too.