New Sapphire X21/X22 Enviro400 MMC's are now in service.
Arriva North East: 7546 / YX17NNV by Matthew Jimmison, on Flickr

One thing I noticed when I rode 7544 was that it had frames fitted to the panels above the windows but had seemingly been removed prior to entering service, guessing it will receive interior branding in this area at a later stage? Also the next next stop announcement slides advertise stuff like WiFi, contactless payments etc. but also includes advert slides for MAX service X12 and Cross Pennine service 685/X85.