I'm keen to know what route this X75 will take. Maybe it will follow the X84/X85 route from Newcastle to Heddon on the Wall, and then go to Ponteland from there? Logically it should follow Ponteland Road, but GNE don't run any services along there, bar the 42A which doesn't come from Newcastle. Even though its limited stop, it might serve the X77/X78/X79 stood along Ponteland Road, or the 74 stops if taking Stamfordham Road.

Does anyone know what tickets will be available/valid for travel on the X75?

No idea why this X75 is being introduced just for weekends for less than 2 months. Combined with the 74 it could be permanent, even though I know its not contracted and the 74 is.

Five trips each way, but no timetable published yet. Hopefully the service does happen and is successful.