British Airways resumed flights out of Heathrow Airport in London on Friday after the cancellation of over 620 flights in a two day period due to a dispute with a catering company that supplies the airline there.

The airline hopes to get 31 flights, both short-distance and long-haul, out of the airport by midnight on Friday and then to run 40 percent of its long-haul flights and 50 percent of it’s short-distance flights out of the airport on Saturday. Passengers who did manage to get on BA flights out of Heathrow were given food packages and vouchers by the airline because only drinks would be able to be offered on those flights.

BA flights out of other airports did have catering service. The disruption was made worse because around 1,000 BA employees walked out on Thursday in support of the caterer’s action, and flights resumed after those BA workers returned to their posts.

The disruption of flights affected 40,000 passengers on Thursday and 73,000 passengers on Friday, according to the airline. Analysts said that the cancellations could cost BA tens of millions of pounds, with one analyst estimate said that the disruption could cost the airline 10 million pounds per day during the stoppage and a great deal more in the long-term, depending on how potential customers view the event.

BA, meanwhile, said it was much too soon to say how much the disruption in flights would cost the air carrier.