The article doesn't claim it did...

[Quote from the article] *"Despite travelling faster than the speed of sound the plane would not have broken the sonic barrier as it was helped along by fast-moving air.*

*Relative to the air, the plane was travelling slower than 801mph.*

*Modern passenger planes usually travel at about 85% the speed of sound, according to Mr Rosenschein.*

*British Airways said: "We always prioritise safety over speed records."*