Where do the GNE Cruise Ship special shuttles run to/from which serve the Port of Tyne cruise terminal?

Obviously each cruise has an array of excursions and day trips that its passengers can pre-book and go on which are usually operated by various coach operators, but I am interested to know more about the operations that GNE provide.

Where do they go?
Are they provided Free to Passengers and Crew?
I presume they are quite regular throughout the day of which a cruise ship is in dock?

I visited Port of Tyne Saturday, Sunday and today - as there has been a Cruise ship in, todays ship the Seven Seas Explorer being the biggest out of the 3 and probably the most expensive and luxurious.

The cruise in port yesterday was a Thomson Holidays cruise ship 'Thomson Celebration' This Cruise actually departed from Port of Tyne, rather than being a Port day,
I did noticed several GNE buses come and go - I think one was a corporate Scania Solar and 2 others were Blue Arrow liveried Solars.

Since there would not be any day passengers coming and going from the ship yesterday, as passengers would just be checking in and boarding, again what service do the GNE shuttles provide on Check In day! Do passengers arriving for check in, use these shuttles with their luggage to get to the port, or are they mainly used on these days by Crew members having time away from the ship.

Are the shuttles all operated by Percy Main depot with PM drivers or do other depots/drivers get involved?

Thanks in advance.