In message , at 12:28:42 on Tue, 4 Jun 2019,
Graeme Wall remarked:

Brentwood is interesting, because while still in Essex, it became
simultaneously the "first place in Essex" for people looking outwards,
but "the start of London" for people looking inwards.
Shenfield is to Brentwood, as Hove is to Brighton.

I've never heard it referred to as Shenfield-Actually.

While not using that exact phrase, they have long corrected people who
attribute them as "Brentwood" residents. Unless of course they live on
the posh private estate in Shenfield (it's a bit like St Georges Hill in
Weybridge) when they might say "Hutton Mount [actually]".
--
Roland Perry