I don’t think it’s fair to accuse someone of lying, there is a human behind them tweets rather than “Thorpe park”, maybe the tweets should have pointed to the information in the app that states the queues will close early but don’t think it’s fair to be calling them liars.
They seem to close the queue so that the ride isn’t operating too long after park close, for what ever reason that is, so I suspect that makes it very hard to actually give a time it will close, when I joined around 8:25 there was lots of people congregating around the entrance / area to try jump In for that last ride so I do see why it’s difficult in that respect to set a time well in advance.