Good overview. It reminds me of a night shift on the last day of the month; I was supervising. The airfield manager had informed me that due to some poor weather earlier in the month, nobody had any night quota slots left to use on late departures, so we had to prevent any departures after 2330 that night.
However, as just half an hour later was a new month (0001 on the 1st), that meant all the airlines had a full quota again, and so we could allow departures
I have had similar when in my previous job at LHR, think it was a saturday night trying to get a late departure away and called the airfield ops manager and they said it couldn't go just yet and had to wait until 0001 as it went in to a new week!
One silly thing about the noise rules was with a late running arrival and it was hammering down the approach to land before 2330, however if it didn't it would have had to go around so would have actually made a lot more noise thundering over London on the way to Stansted rather than landing a minute later!!