Ummmmm, sorry but I *really* don't think the above is quite right at all TBH
Firstly: Advance Tickets
almost always have a line in the Ts&Cs which prohibits Break Of Journey (other than for any necessary change of trains) and
usually specifically state "is not valid for starting or ending a journey at intermediate stops" or words to that effect - i.e. it is
only valid for use between the 2 places printed on the ticket on the specific date/times printed on the ticket ! Here's an extract from the Ts&Cs for the Advance Tickets that I generally buy for almost all journeys other than to/from Glasto:
QUOTE
Non-refundable ticket, only valid for the date, time and trains specified.
You must travel on the date, time and trains specified. You may not start, break and resume, or end your journey at any intermediate station except to change to/from connecting trains as shown on the ticket(s) or other valid travel itinerary.
Secondly: As Advance Tickets
technically do not normally permit you travel on any other train than that printed on the ticket, doing so leaves you open to getting caught and being charged for an appropriate standard ticket for your journey as your Advance Ticket will be invalid. It
may be possible to claim that you missed the 'right' train due to a service stylee issue and therefore get away with travelling on an alternative service but it's by no means clear that you can. If anything, it's usually strongly implied that you can't. Unless you buy travel insurance (usually an additional £1 at the time of ticket purchase) or have an existing policy that covers you then missing the 'right' train is entirely YOUR problem and not a problem for the train operator ! In any case, I would seriously doubt that delays at Castle Cary for instance would actually qualify as "Service Delays" for which the train operator will officially allow you to use a later train if necessary and may not even be covered by insurance either. It's more than a bit like claiming the traffic on the M25 or at Heathrow car park made you miss your el-cheapo flight therefore the Airline should allow you travel on a later flight at their own expense isn't it ?
I always travel by train and I've seen peeps getting mucho hassle on their journey for being on the wrong train and ultimately getting charged for a standard ticket. However, if you're on one of the Glasto Specials or simply have an 'understanding' guard then you'll probably get away with it. Similar story if you're on a long(ish) distance intercity stylee service but for more local trains and esp for any connecting services ... prepare for hassle I would suggest if your ticket is restricted to a specific train at a specific time and you want to travel on a different service for some reason or other. Do also bear in mind that tickets are always *very* well checked at Castle Cary so no chance of even blagging your way on to the platform unless the guys are entirely satisfied that your ticket is totally valid for your journey. They don't have a huge F/O great booking office placed outside the station over Glasto weekend for no good reason

As no one posting on here is really in any position to give a
definitive answer, make sure you check the Ts&Cs when buying your tickets to ensure that they are suitable for you. There are deals to be had but you need to be careful and an "open" return is defo the way to go if you can and providing it's not silly money. The Ts&Cs for different ticket types from different operators are often significantly different so you really do need to check the requirements specifically for YOUR intended journey I would suggest.
It is possible to get a specific train from Castle Cary if necessary but it's by no means easy and would require plenty of planning with no doubt lots of hanging around. However, it's usually pretty well organised down there so if needs be, ensure you get there in plenty of time for your train then talk to the guys running the show when you arrive if getting on any old train would seem to be a problem because they will be able help and should allow you to jump the queue if needs be.
BOTTOM LINE: Always check the small print and all that rather than making assumptions or just believing everything you read on t'internet
Edited by mikeb, 30 May 2010 - 08:10 PM.