It would be useful if you could upload a copy of all the paperwork you've been sent about going to court (but do redact any personal information before uploading).
Generally speaking, bylaw convictions are not entered into the Police National Computer and ordinarily won't show an basic or standard DBS checks. That said, a bylaw conviction
is a criminal conviction and also a matter of public record and organisations do sometimes have other ways of finding out this sort of information.
For most purposes the conviction will be considered as spent after one year. If you are asked if you have an unspent conviction then I would always advise being honest about it. A bylaw conviction for a minor railway ticketing matter won't normally adversely affect career opportunities.
The charity Unlock is a good starting place for more information:
For people with criminal records.
unlock.org.uk