Advance Single Train tickets when 1st leg is cancelled

[Choux]

I need to do a long day return train journey on Tuesday. The second leg is on Northern trains who are rather unreliable. I did the same journey a year ago and the two Northern trains were cancelled so I had to wait an hour each time for the next one.

Ticket options for this trip are:

Get a ticket for the full journey on the trainline.com which will cost £232. The Northern train legs may still be cancelled but on the return I would have a full through ticket so presumably Avanti would be ok with me being on a different train to the one listed on my booking.

Or

Get two advance singles to and from the connecting station and then a day return with Northern from the connecting station to my destination. This costs £120 so is a whopping saving of £112. But my question is IF the Northern train on the return leg is cancelled and I miss my Avanti train, will I get grief on the Avanti train for being on a different train from the advance single I have bought? I will be able to show I had a 45 minutes to spare if the Northern train had run so it is their fault I missed the Avanti train. Will that be ok or will Avanti make me buy a new ticket?

If you're buying them as individual journeys, you'll need to buy a new ticket. Could you get advance for the Northern section and anytime/off peak for the Avanti part?

You'd be more likely for them to let it go if it was the same provider.

Yes that is my concern. I get the Avanti leg a lot at weekends and rarely have my ticket checked. But this is midweek so I don't know if the ticket would be more likely to be checked.

Currently the price of the advance single on the Avanti leg is £42 on both the train I plan to get and the train after. An off peak single costs £81 so a bit like buying a ticket for
both of the trains.

But IF i was delayed and IF the ticket was checked and IF they did make me buy another ticket it would then cost me an extra £42-£81 depending on what the cheapest ticket is.

i think i might buy my ticket to get there now and then keep an eye on both the Avanti prices back and check if there are Northern delays on Monday. i could even buy the ticket back home on the day. Have never done that before.

If you were made to buy a new ticket on the train, it would be the full standard single fare. They aren’t obliged to sell you the cheapest if you didn’t buy before you boarded.

Ah thanks for telling me that as I didn't know you couldn't get an off peak single on the train itself.

I could buy my ticket on my phone before boarding once I was on the northern train and knew when I would get to the connecting station.