It be put out to tender again. But I highly doubt that no one hasn't put in to run the contract. It doesn't say one operator must run the service on their own as basically it's a contract to organise it too, so say GNE won it, they probably provide say 20 buses, and hire in other operators to take up any runs that are spare or even lend drivers from other operators or other parts of the Go-Ahead Group.

If it's say Stagecoach for example, they could draft buses and drivers from around the UK especially for locations that usually have a peak summer timetable and since the summer is over, they won't need as many drivers so can offer them an incentive to work elsewhere. Similar situations occured during the Olympics and the Commonwealth games.

It doesn't even have to be a local operator, for example, Lothian Buses for example could think, oh I have some of that contract, divert their latest deliveries to a temporary depot and run the service from there. Once the service is finish the buses go off to Edinburgh.

It happened in Manchester during the GNW strike, I managed to travel on a coach from Edwards (Who has depots in Wales and Bristol) where their drivers were lodging locally. Travellers Choice and Midland Classic were another 2 operators helping out too.