You would automatically be entitled to take the next train complying with the ticket's route or operator restrictions. In this case that would likely be the next Chiltern service.
TOCs generally also have a policy of allowing you to take the preceding service.
The amount of notice given for the cancellation is immaterial; either way if your booked train is no longer running, you obviously can't take it!
I didn’t want to start a new thread so I’ve jumped in on this one as I have a dilemma where I have an Advanced Senior day return this coming Weds 8:12 Arundel to London Victoria.
Dirt cheap the outward (& return) timed travel £3.95 each way but with the ‘ASLEF situation’ my outward has been chopped. I need to be around the corner at Victoria station for a medical appointment at 10:00 & this train was going to arrive at 9:45
The train before had an outbound fare of over £38 (peak) & the later train gets me there too late so this morning I call Southern Customer Services asking what are my options as I don’t want to get fined etc & I know normally I can get the next later one (no good to me)
They put me through to National Rail customer service & with the guy back & forth for advice tells me I can get the earlier train (peak) & just explain to the OBS that due to current ‘ASLEF issues’ it shouldn’t be a problem…..shouldn’t isn’t good enough for me for obvious reasons.
Let alone the Gateline exit at Victoria won’t let me out (another problem)
The so called advice I’ve been given I have no confidence in, any advice from forum members in the know would be gratefully received.