PHOENIX — Kyle Shanahan isn’t quite sure whether the 49ers will be traveling forward or backward when they make the trip to Melbourne, Australia, to open next season against the Rams. He just knows they will be spending nearly a full day on an airplane. “I think we’re going back in time or into the future. I think we gain a day or lose a day,” Shanahan joked on Monday at the NFL’s annual league meetings in Phoenix. “I’m not sure which one yet.” For the record, the Rams and 49ers will actually