Strictly conjecture but seems to hold true based on times I've seen. Most everything sent to (or passed) the midwest, transfers in Chicago (Chicago Heights actually) from train to other trains or trucks. I live within 20 miles of The Heights and the Saturn Store I deal with (one of 6 owned by the same guy) says their delivery times (16 delivered) has been an average of 8-10 days from invoice.
So depending upon your ditance from Chicago ---