Approaching Basrah last year, tower advised us that the last 2000m were unavailable as a rocket had landed and blown a hole in it. Quick recalculation of landing distance and autobrake setting, no problem.
As said do the maths, then no problem. Our alternate Baghdad also had a 'mystery' hole appear on the main runway!
These events as in Accra when correctly handled, make this job what it is.
Good work by BA, proving that using commonsense and technical knowledge prove their worth.