Im in London This Saturday(28th May), possibly going up to Kings Lynn and back, and on way out would like sample a 720 on the Liverpool Street-Cambridge services, have not been on one yet, would prefer the limited stops, than all shacks. So are most services now 720’s? or is it bit pot luck, if something else turns up on a service? Ill be going probably between 4pm-5.30pm approx, so any diagrams etc be handy, thanks.