Originally Posted by
Often1
It's not just the "door," it's when the flight is closed. Doors can be opened and closed quite quickly. But, once the flight is closed, the numbers have been sent off to dispatch for weight & balance and other purposes.
I realize this difference, and therefore have a pretty high threshold when it comes to playing the "trip in vein" card after boarding. That having been said, 3 hours is my typical limit during the summer months; I always give crews a heads up about my limit after the first ~30 minutes passes.