So it turns out the Tramlines leak was right after all and that Kasabian & Courteeners were the other way round.
My position remains the same - I like Bloc Party much more than Courteeners, so would've been happier if those two were the other way round so I didn't have to pay for an extra day. Incidentally, is only one support for Bloc Party so far added?
Though looking at my records, I booked my ticket to Truck 2019 in May 2019 2ish months before it was due to happen in the final tier of tickets. So I've got time. Plus tbf I still like names on there. Even if my knowledge of the lower down names is woeful.