On this episode of Day Tripper, Justin and Austin travel back to September 13 for two very different moments in Beatles history. We look at the 1965 U.S. release of “Yesterday” backed with “Act Naturally,” a single that paired one of Paul McCartney’s most enduring ballads with Ringo Starr’s country-flavored showcase, and then jump ahead to the release of the Yellow Submarine Songtrack, which brought the music from the Beatles’ animated classic back into the spotlight with newly remixed versions. Two releases, decades apart, and another quick trip through Beatles history.