Short answer: yes, but with asterisks. Long answer: plan like a pessimist, hope like an optimist.
If you really need to get somewhere, book a ticket in advance if possible. Some operators require reservations on holidays. It’s insane, but it’s real. Don’t be the person who shows up to a queue of 400 people at King’s Cross.
And hey—if you’re just going for a walk? Maybe skip the train. Walk to the park. Enjoy the quiet streets. Because on New Year’s Day, the best journey is the one where you don’t have to ask yourself, “Are the trains running?”
Just stay home. Eat another leftover mince pie. The trains will be there tomorrow. Probably. But don’t quote me on that.