As all the previous posters have noted, these are things you can't control and the LGW l/h fleet generally runs smoothly, so I wouldn't worry about a cancellation on the 9th when your flight is in 2 weeks time!
If it helps set your mind at ease, the reason for the cancellation was a LGW-MCO flight on the 8th diverted to TPA due to weather at MCO. The aircraft then sat on the ground for 24hrs and operated the normal TPA-LGW service back on the 9th. With 1 plane stuck in the U.S. for 24hrs and 2 of the LGW fleet having minor maintenance in the meantime, BA didn't have spare aircraft to send to TPA on the 9th, and the cancellation was only 1 way (LGW-TPA) which passengers could be accommodated on other flights.

Pilot37