(05 Dec 2021, 9:33 pm)Andreos1 wrote The grey spare livery is the one that stands out for me. 
Maybe it's because it isn't too much of an identi-kit copy and paste that looks like something ran by another operator.
https://www.flickr.com/photos/27974644@N07/51523176814
https://www.flickr.com/photos/york-bus/42835576360