I wish LRG would have been clearer about Celeste being complete before the preorder ended. All we knew was there was going to be DLC so that it looked like LRG's release wouldn't be complete which kept me and my friends from preordering. Generally, my view with games grom Iam8BIT and LRG is that if I'm going to pay a premium for a physical copy, it best be a complete on-disc release. Many of us didn't think Celeste would be ... until way after preorders closed.
Oh well. I guess there's the Best Buy copy but wanted it on PS4.
Manufacturing wasn't originally going to get delayed for the DLC because we didn't know about it's existence until pretty late in the process. Community feedback after the preorder closed led to the decision to delay manufacturing so that it could be included on the cart.