Although movies are not really shot on film anymore, the phrase, “Check the gate” is still used on set to mean “Check the card”—in other words, make sure a take recorded properly before the equipment is broken down and the scene finished. In Hummingbird Agile, the gate is the fourteenth day and last day of the circuit, where all work must be completed. It’s like “Checking the gate” to make sure all the work for that circuit is done before breaking down the set and moving on to the next circuit.
Since day 15 is a rest day, where the hover closes out the current circuit and refocuses their sights on planning the next circuit, there is no last-minute work that should leak past the gate and into day fifteen. It is a pencils-down day for the crews to complete and check-in their work as well as perform regression and integration testing by the end of the day.