Would it do the extra stop at Alnmouth, I asked. No, they said. But since I was ultimately heading for Wooler, which you can get to by bus from either Alnwick or Berwick, and I wasn't going to make the 10.20 bus up Coquetdale, I decided I was better getting the 8.30 to Berwick and making a new plan from there than waiting for the 10am Alnmouth train.
So I've explained this to the guard on the train, and he's said I can go on to Newcastle and back if I want, and I've got to Berwick and I'm walking along the platform towards the stairs when they make a completely unintelligible announcement and then the platform guard is yelling at the top of his voice (much more effectively) for any Alnmouth passengers to get back on, because they've suddenly decided they're stopping there after all.
I'm not sure why they couldn't have worked this out sooner - there were quite a lot of people waiting at Alnmouth, after all.
But anyway, I got my bus ride from Alnwick to Rothbury and Alwinton (which has shot straight into my however many best bus journeys in the world - I love that middle strip of moorland and low ridges, halfway between the hills and the coast), and my walk up Coquetdale, which was lovely, and had tea and cake in Barter Books without going mad (it's a bit overwhelming), and made it safely to Wooler.
What will go wrong on the way home, I wonder?