Great idea Dave, more than happy to help out with my photos from 1999-2005 and then from 2015 until the present day. First up are a few photos of different formations during 2015 and 2016.
First up is the PGA rake, which was the norm for the 1990's up until 2016 in a variety of liveries Note the different height bodies and debranding on some wagons with a large black rectangle applied.
66193 Attleborough 20/02/15 by Ryan Hayward, on Flickr
66117 Eccles Wood 30/03/15 by Ryan Hayward, on Flickr
66040 Hethersett 17/04/15 by Ryan Hayward, on Flickr
During 2015, rakes began to become a mix of old PGA's and freshly repainted HKA's (I think). The quantities of each varied from a couple of PGA or HKA's through to a 50/50 split. I never managed to photograph a whole rake of just HKA's, maybe Dave managed to. The HKA's were not a particularity permanent fixture, lasting only few months during the summer of 2015.
66156 Browick Road, Wymondham 28/07/15 by Ryan Hayward, on Flickr
66149 Besthorpe 29/06/15 by Ryan Hayward, on Flickr
66075 Ketteringham 27/07/15 by Ryan Hayward, on Flickr
66169 Spooner Row 06/07/15 by Ryan Hayward, on Flickr
And the new arrivals in 2016, the very grey JNA or HOA wagons that started in April of this year.
66067 Hethersett 20/04/16 by Ryan Hayward, on Flickr
66127 Hethersett 08/06/15 by Ryan Hayward, on Flickr
66019 Hethersett 06/06/16 by Ryan Hayward, on Flickr