Looking at it, it's just scrapping them as a registered route and thus they can't carry local passengers. The routes are still bookable for dates after the registration change, but you can't book the local journeys.
Across the board, National Express does seem to be cutting back on 'local' passengers, I note a number of London Service Permits to reduce the number of services which fall into the LSP and as such reduce the number of services which then can take local passengers between Heathrow and Victoria (404, 406, 408, 423, 460, 501 and 504), and Golders Green/Finchley Road and Victoria (422, 440, 540 and 560). Plus the recent changes to the 170/171 which have banned local travel.
In the case of the 717 and 777, I doubt people are really travelling locally on these routes anyway, and if they are the numbers will be small. Registering the route can lose flexibility (as changes become subject to registration timelines), and you really should be held against the Traffic Commissioners punctuality rules.