On LHR-EDI route alone there are 4 canx listed for tonight - BA1446, BA1452, BA1454, BA1458. The BA1462 is expected to arrive two hours late at 2237 and is still listed as being operated by a 757. BD has cancelled 2 LHR-EDI flights. If the other routes are as badly hit (and they certainly appear to be) then I can only assume the hotels at LHR will be extremely busy tonight.