British Airways halted ticket sales on some short-haul services out of London Heathrow airport through to make room for passengers who’ve had their flights scrapped amid capacity caps at the hub.

The unit of IAG SA said the move follows Heathrow’s request for carriers to limit new bookings after introducing a limit of 100,000 daily departing customers on July 12 to help cope with a staffing crisis.

“We’ve decided to take responsible action and limit the available fares on some Heathrow services to help maximize rebooking options for existing customers, given the restrictions imposed on us and the ongoing challenges facing the entire aviation industry,” a BA spokesman said by email.

The UK carrier has canceled about 13% of planned capacity this summer due to a shortfall in its own employees and the steps imposed by Heathrow. Airlines and airports across Europe are struggling to meet demand that’s rebounding strongly from the coronavirus crisis, with the London hub warning last week that the situation could persist through next summer.

The cap on sales imposed by BA is similar to measures adopted by Air France-KLM’s Dutch unit in late May as signs of travel chaos this summer were emerging. Like Heathrow, Amsterdam’s Schiphol hub along with London’s smaller Gatwick airport have also imposed curbs on departures.

Capacity caps may have crimped passenger numbers, but they’ve also bolstered fares in a sector where demand was already close to matching supply on many routes.

An economy class seat with hand baggage only from London’s smallest airport, City, to Frankfurt on Aug. 2 was as much as £417 ($512) one way, although return fares were considerably cheaper at about £190, according to a search on BA’s website. A flight to Milan Malpensa from London Gatwick was slightly cheaper at £354.

Source: Civil Aviation Authority – Qatar