Been discussed here more than once previously but basically this is how it happens.
1. Media is given the story that all operators are reduced by a figure, typically 20-50%, for certain hours.
2. BA then cancel way more than this standard percentage assigned to each operator, for reasons that no informed commentators can understand.
3. As a result remaining operators then find they can operate, albeit with delays, 100% of their normal schedule.
4. Statements in the media next day that BA has cancelled "some" short-haul flights to protect their long-haul flights.
5. Analysis shows this is not so.
See here regarding the last time this happened :
http://www.pprune.org/airlines-airpo...ml#post7642276