Look at the setlist from the night before. If they ended the previous show early, something’s up. Maybe Liam’s voice was shot. Maybe he just didn’t fancy it. If the previous show went long, they’ll likely be early the next night. It’s like a weird pendulum of brotherly chaos.
One hilarious instance: In 2005, Liam threw a tambourine into the crowd during the first song. It hit a fan in the face. The band stopped. Liam said, “That’s it, I’m off.” They did not come back on for forty minutes. He got the tambourine back, though. True story.