Richard J. wrote

I'm not convinced that the 1949 Act has been completely repealed,
piecemeal or otherwise. The Crown Prosecution Service website
contains
this:
"Railway Offences: Such offences will involve using a variety of
statutory offences dating back to the 1840s. ... References in
Sections
54-57 of the British Transport Commission Act 1949 shall include
references to any successor of the British Railways Board."
It then goes on to describe offences such as trespass (section 55)
and
damaging trains (section 56), indicating that the 1949 Act is still
in
force. The page was last updated in December 2007.

http://www.cps.gov.uk/legal/p_to_r/r...ransport_offen
ces/#Railway_Offences
(from the CPS home page via Legal Resources, Legal Guidance, then
look
in the A-Z list for Road Traffic Offences (sic), and under that
'Transport Offences', 'Railway Offences'.)

But to prosecute those offenses all that is required is to prove the
Act was passed and amended.

It would be up to the defending side to find the repeal if it exists.

In many cases a more general offense like Criminal Damage would cover
the ground.

--
Mike D