Going back further in time, to when the WLL was newly electrified from CLJ, there was a period when the CLJ-OLY peak SX shuttle was (on paper) a 455 and another period (on paper) a 4Cig.
I never managed neither 455 or Cig at that period: I had a 4Vep one way one day, and another day, a 3H the other way another day that was after the 4Vep, when booked EMU not DEMU. It /was/ a DEMU for a period up to electrification, but this was some weeks after EMU were the norm.
The other thing to note is the 21C 455s were from SN (i.e. from the Central side) whereas the 20C 455s were from the South Western side, as it was SWD provided those trains then.
Which is another example of why I say again and again do not assume that paper diagrams are actually what happened (q.v. 304/310 thread about LH cobblers).
It is interesting how that former SX peak service morphed through time with the way the route developed, the number of different train types I have had to/from 0lympia NOT counting railtours through the place that will grossly distort the picture
I make it
313
319
350
377/2 *
377/7 *
373 = not on a railtour
378 (3car and 4car and 5car)
455
456 - this was 2x456 vice 455 one Sunday - I still owe the controller who txtd me a pint for me to go for that one
4Vep
3H
3R
33+LH
33+TC
73+TC
73+TC+73
25 / 2x25 (motorail)
47 LH
50 LH
* IMHO a 377/2 and 377/7 are sufficiently different internally to count one type each
Someone will be along in a minute and wibble about 09s - this is largely a myth distorted out of all recognition from fact - there were maybe a miniscule number of such workings, maybe only 1-2 dates, if that, and at least one person I knew who alleged to have had two different ones was b**ls**t**g yet these alleged workings seem to have been believed. Anyone saying otherwise please provide _hard_ evidence.