Jayco builds in "similar model" batches in each of the towables final assembly plants, and similarly back up the supply line in the cabinet, furniture, frame etc shops. So if the model you ordered was produced shortly beforeyou ordered it, the plant may not get back to that one again until rotating through all the other model lines and types for which there are orders.
Jayco may make the Starcraft in its own plant (not sure, didn't own the brand when I last toured) but would most likely follow the same production management scheme used in Jayco plants.
If the factory. gave the dealer a production date, that date is likely good. After that you are waiting for transport, in a slow season for RV transport.