This week I bought a Day Return (CDR) to Guildford and first looked up
the fare on

http://brfares.com

And noticed not the usual 'restriction B1', ie after 09.30 but rather
B4 = after 08.45 which meant I could not only travel earlier but use my
Railcard earlier.

Try, for example, Esher to Guildford or indeed Esher to Farnborough
(stations)

I am cross-posting this to uk.railway in the hope that someone can
explain the policy and/or history here.

I note that Surbiton to Guildford is 'restriction B1' as is Esher to
Godalming but
Woking to Guildford, Godalming and stations to Portsmouth are all
'restriction B3' = after 09.00 thus providing another case where buying
two tickets can be useful.

Of course, if the restriction code was printed on the ticket I might
have spotted this years ago.

--
Mike D