I had been tracking the progress of the up Three Peaks Challenge ecs working on RTT whilst at work and escaped in their van when it was passing Long Buckby. This gave me enough time to get to Mill Road bridge in Northampton. 57307 'Northern Princess' leads the 5Z51 10.50 Crewe to Euston composed of a ragbag collection of stock some of which could have been seen at Crewe, see....
https://www.ontheupfast.com/v/photos/21936chg/28607649404/various-coaching-stock-crewe-south