I enjoyed The Prisoner, actually.
https://www.nationalrail.co.uk/service_disruptions/172038.aspx is what I'm passing along to her.
I'm also going to suggest she get a room in or near Manchester on arrival, and get a good night's sleep, as she will have been traveling all day. Then if she wants a car she should book it months in advance. I am going to warn her to not try to bring a car into London, as it'll be useless for her purposes there.
I'm also suggesting she might want to see if Salisbury/Stonehenge/Glastonbury are of interest, and staying there. (Perhaps she can find a tour from one of them over to Wales? If not, I'm sure she could get one from London.) I'm also going to suggest she increase her time in England from 3 days and cut her time in Scotland down from six. From London she could take a tour to Canterbury for a day. There's also Westminster Cathedral, the British Museum (and several others to choose from), a day to wander around shopping, etc. It's my understanding York has a nice Christmas market, so she might want to take a day train up to actually get to see the countryside, then stay in York before coming further north. Or she may really want to do the Caledonian Sleeper - if she takes the Highlander it'll take her up to Ft. William. She says she definitely wants to see the Highlands, and has been warned that her ability to do that will depend on the weather. She's going to base in Edinburgh for a bit, I think, and take some tours out.
https://www.visitscotland.com/holidays-breaks/christmas-winter/ She theoretically will be over here with us for Christmas, and then heads to Ireland. She has six days planned for Ireland. I'm not sure what she can do in Ireland for six days in winter, other than wait for buses, but....
She's still planning, so hopefully the info I pass to her will be of help.