I ordered the same model on 6/11 and mine just shipped last night. I'm not sure why but the stock base model seems to be the slowest to ship. Apple's estimated delivery date is July 5th and my original delivery estimate was June 29-July 6th so these models are barely making the original delivery estimates.
Hopefully they speed up soon!
Probably because they also have to replenish retail stock with these models as well. I feel like BTO would ship quicker since those arent for anyone but those who order them.