The last two words in that sentence are pretty important "PER DAY"

>"Kaye’s solution is to cap Heathrow passenger numbers at 100,000 per day for the Summer period" ... "the closure for sale of all flights departing from the airport until 11th September a reduction in the current passenger cap from 101,500 to 100,000"

meaning every day until 9/11 1.5k people aren't getting a seat they paid for