Had a trip from Clapham Junction to Highbury & Islington yesterday
afternoon - a bargain £1.10 with Oyster. Can anyone help with the
following queries?

Why are most LO station name and platform number boards marked with
'This is a temporary sign'? What's wrong with them?

New class 378 S- and 3-car stop signs are also appearing, some of
which are only 2m from the existing signs. I understand that there is
a need to move some NLL station S car stop signs ready for 4-car
operation, but why the mucking about on the WLL?

Compressors on the 313 I rode were incredibly loud, more so than on A
stock. For whatever reason the popping noise that I normally associate
with the driver cutting power is also made when accelerating - I can
rule out third rail gaps as it happens when leaving Willesden Junction
HL. I think Southern will live to regret taking on this fleet!

Judging from comments and queries from other pax e.g. "does this train
go to Camden Road?" overheard at CLJ, I think the assumption that most
pax are doing 2-3 station hops is incorrect. The three other occupants
of my bay from Willesden Junction hadn't left the train by Highbury.
The train - 17:30 ex-CLJ - had plenty of standees but was not crush
loaded. A non-scientific survey, but in conclusion seating in the 378s
will be totally inadequate: was a compromise of 2+1 seating considered?