The cover dates were typically set two months in the future from the actual publication and release date, so the magazine would have hit the newsstands in November of 1977. (The first issue of MAD hit the stand in August 1952 with a cover date of October–November.)
That five-month interval actually was a respectable turnaround given that no one knew just how big Star Wars would become when it was first released, and MAD already had their stories lined-up and in the works months ahead of their release dates.
