Just trying to work out the chronology of the Class 302/306/307 fleets on the Great Eastern Main Line post-war, as I'm a bit confused with it all, especially with the 302/307 fleet. Correct me if I'm wrong, but the 306s were effectively the Shenfield Metro fleet from new until the 315s came into service in the early 1980s? With the 302s and 307s, were they used on the Southend services and branch services from new until cascaded 312s and the new 321s replaced them? Were the 302s then sent over to the "Misery Line" to supplement their own fleet? That being said, I've seen a few photos of 302s running on the Lea Valley Lines along with 305s, which has now got me thinking "I thought the 317s were supposed to replace the 305s on the West Anglia side of things"? Sorry if it I seems like I'm rambling, it's just the whole first-gen AC EMU side appears very confusing with regard to operations, Network SouthEast sectors, and replacement.