They can enter your order into Order Workbench at any time. Unfortunately, unless they have an allocation, your order will just sit in the preliminary tab until GM gives the dealer an allocation to fulfill your order with. Every Thursday a new DOSP cycle begins and it closes Friday at 9:00 PM. If your dealer has an allocation with acceptable constraints, your order will get placed with no issues. If they got an allocation and weren't offered the constraints to build yours, they can still prioritize it to try to secure the constraints. If a dealer that received the constraints passes on them, the constrained options go back into the pool and your order could be pulled and sent to production.