It is a system glitch with DVC reservations. To use 180+10 you need to call. Unless booking an in demand type location, I've never had problems just waiting until 180 days from check-out date.
I can book my 180+10 days as long as I am logged into my MDE account and my DVC reservation is also already linked to the MDE account. Have you tried that?
I can book my 180+10 days as long as I am logged into my MDE account and my DVC reservation is also already linked to the MDE account. Have you tried that?