Flight was delayed by just under an hour. There was good communication about this though, text and e-mail. The flight was quicker than initially advertised so we arrived earlier than expected.
The walk from the main area at terminal 2 in Heathrow to the plane at the B Gates can take 10-15 minutes depending on the speed you walk, so be aware of that.
It is worth paying to board quicker as well, as the overhead compartment fill up quick.