Will itineraries ticketed before Nov 16 still be governed by the old rules & redemption levels if one wants to make a change to the routing within the same geographic zone?

Specifically, can I change a routing that under the old rules would require the same amount of mileage but under the new rules would have different redemption levels? For example, I hold a JFK-NRT-BKK ticket -- can I change that to JFK-NRT-CGK without being hit with the new mileage levels?