It isn't just random. Since their introduction they have had booked work to Cambridge and Kings Lynn.
Haven't they pretty much always run the same services to Cambridge? - eg as set out in this message from 2014 - the three peak 12-car workings.
Due to travel Cambridge to Liverpool St Sat 5th and back Sun 6th, considering taking advantage of advance tickets. Is there any way of knowing which services will be using 379 Electrostars?
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