Where is your starting point?
I have often felt that the most stressful part of any bike adventure is the train journeys to and from. They take a lot of organising and there is always the element of risk to journeys on what is fundamentally a fairly unreliable means of transport (trains in the UK). I have logged some real nightmares we have had on train journeys involving bikes, and camping within easy reach of the necessary station where we are booked the following day, elsewhere on this august forum.
My most recent effort, in the summer of 2019, involved meeting friends from Merseyside in Newport to ride the Lon Las Cymru, and then return to our various abodes by train. The journey out wasn't too bad: I travelled from Essex and had no problems crossing London and catching the train in Paddington. The others were already there to meet me. When we came back, it was a different story: we all had reservations from Holyhead, but at different times. Mine was the earliest and, whereas the others were heading for Chester, I was staying overnight with my brother in Shrewsbury, so we chose not to ride together. I pressed on, and the weather was so awful that I was glad I did. Really, really wet. I got to Holyhead with enough time to spare that I could buy myself some lunch in a greasy spoon. I got to the station in plenty of time.
Shortly before my train was due to leave, one of our party boarded. I can't recall what time his reservation was for. The other two waited for a later train: I didn't get to speak to them at that point because I was already in the carriage and the train was due to leave. Eventually we set off and when the guard came round to check tickets she said "It's a shame the others didn't catch this train as when the weather is as bad as this we just want to get people home, and never mind the reservations." I would say that it depends on the train operating company, but I have often found that there's quite a disconnect between the official policy of the company and the attitude of the people whose job it is to operate the trains. Virgin have always been totally obstructive jobsworths in my experience. Arriva Trains Wales staff were always much more co-operative.
However, we ended up in Chester in the pouring rain and it was at that point that I found out that my train on to Shrewsbury had been cancelled because of flooding/tracks sinking into mud/that sort of thing. The driver of the replacement bus agreed to take my bike. Otherwise, since I already had a ticket and a bike reservation, the train co would have been obliged to find me a taxi (I've had this before on other occasions).
Since covid I've only made two train journeys: one was when I bailed on a ride because my arthritis was playing up and the weather had taken a real turn for the worse, and the other was when on tour last September with AndrewC and Canardly. We were due to cycle form Ipswich to Norwich, but the forecast was for really wet weather so we got the train to Norwich and spent a soggy day seeing the sights, sitting in pubs and cafés and generally whiling away the time until, as late as possible, we put drenched tents up on a drenched campsite.