I did Race to the Stones 100k in 2019 – it's a lovely undulating route and was a perfect ultra entry point for me (though a big step, as I'd never even run a marathon before that...). I suffered from hip pain throughout the training, and then knee pain about a month before the run, so stopped any long runs in the month leading up to it... before that point, I would run a fast 5k, 2 x comfortable 10k runs, and then a steady 30k run weekly. I probably should've done more, but I felt like those runs were already a squeeze.
I ran one 50k run (the longest of my training) about 6 weeks before RTTS, and kept stretching and rolling throughout, as well as exercises for my hips as suggested by a physio. Probably not the best advertisement for training, but it definitely felt like mind over matter for me!