(03 Aug 2015, 10:34 pm)R852 PRG wrote It has been since mid-July: https://m.flickr.com/#/photos/127739730@...991401614/ (although there are no Driver Training stickers like the other examples, the modified seats can be seen and the bus was parked amongst other training vehicles at the time).
It has been in for longer than that. It's entry into the Training fleet was first noted in the Go North East website in the update for 15th June.