Bit out of touch with the UK rail scene but whilst waiting for the Foxton spoil train, what I believe, is the new order, 8 car 700 053, trundles through Meldreth on a test /driver training run towards Cambridge.  I did later see a 12 car version but was too far way to get the unit number.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/11905963@N06">XPinger (Chris Sutton)</a> from Rotorua, New Zealand
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/xpinger/41340629092/">Meldreth</a>