To be clear, you cannot make ADRs 190 days out unless you're staying at WDW for ten days. If your trip is shorter, the number of days you can call for ADRs in advance is smaller. You can only call 180 days prior to your check-in date.
I'm not so sure I'd change my vacation dates due to ADRs, but I would make ADRs as soon as I possibly can, even if I don't know for sure where I want to eat and when. It's easy enough to change them later if there is availability, and if there isn't availability, at least I have something booked.