From the BBC :
.....an airport spokeswoman said. She added that flights had not been cancelled but there were delays.
BA Heathrow arrivals from Manchester (at 0930) :
08:25 BA1385 MANCHESTER DELAYED Terminal One
09:25 BA1387 MANCHESTER CANCELLED Terminal One
11:00 BA1389 MANCHESTER CANCELLED Terminal One
12:20 BA1391 MANCHESTER DELAYED Terminal One
14:25 BA1395 MANCHESTER CANCELLED Terminal One
does the "airport spokeswoman" have the faintest idea what she is talking about ?