To add my 2p, in the bus reshaping plan, the network was to change to a
model of 'trunk routes' linking nodal points (ideally at tube, or
rail/tube, interchanges) with local 'feeder routes' to carry traffic to
the nodal point.

Wood Green was the main model (with Turnpike Lane as the Nodal Point),
Walthamstow and Golders Green were others. I still have no idea why the
128 was changed in it's entirety to W8, but made flat-fare (unless it
was to test the concept away from the 'Nodal' model) even though I used
it everyday for school (both as the 128 and the W8).

So the 'Lettered' routes were basically local services.
--
Steve
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