Wow, that would never happen here. A band not even coming on stage until 1:15am? No chance. Everyone uses public transport in London to get to shows, and that is long closed down before then. All shows finish at 11pm. 11:15 on rare occasions. Most venues don't even have carparks!
Sometimes we get the too many support acts thing, but they're rattled through with 30-minute sets each, max, and 15-minute changeovers.
What this normally means is if the last support band is the "special guest" who are doing the whole tour, they only get 30 minutes as well. And the headliners get an hour. And given that the rest of the support bands are rarely ever advertised, the fans are essentially paying for a short show.
Checking out Arch Demon Choir...