All I know is that the longer The Last Knight is, the worse the reviews will be. If it ends up closer to 3 hours, those 0/10's will be exploding out of the gate.
Based on previous movies, and given how much stuff is apparently in here, I'm guessing it might be on the nearer side to 3 hours, so formally I'll say 2hrs45min.
The same as majority posted close to 3 hrs to fit everything in as so many different sub plots like Optimus in space, walberg's character journey, also Lennox, the kids, Merlin and past events need explaining/flashbacks, maybe time travel, dinobots and autobots on earth journey. A lot of stuff in this film needs to happen it will be a long one for sure