The London to Athens Boxing Day flight ended up stopping in Zurich after the co-pilot fell ill. The primary pilot of the A320 Airbus had intended to fly all the way back to London Heathrow to get the co-pilot medical help. The plane touched down in Zurich without incident, allowing the co-pilot to get medical help. The BA flight later continued to Athens where it arrived nine hours later than originally intended. "The Captain thought the situation was serious enough to divert rather than try and return to Heathrow.

Source: Daily Mirror December 28, 2020 23:57 UTC