I think an important thing to consider is that if your going to take large amounts of vitamin D, you should also be getting enough magnesium to prevent unhealthy calcification.

In the winter, I've taken one time doses of ~40,000 IU every few weeks or so, (always in the morning of course). I remember reading that 40,000 IU every single day for more than 3 months was what it would take for many people to develop hypercalcemia. Because vitamin D is fat soluble, that made me feel pretty safe taking a large mega dose from time to time. The effects of a large megadose are emotionally palpable.

But I will say that the magnesium also seems important. I have a sensitive ankle that was once run over by a taxi and got badly sprained. Last winter, I started taking daily vitamin D without magnesium, and was probably doing about 10,000 IU/day. After a week or so, I noticed that my ankle was acting up more than usual. I took an epsom salt bath (magnesium sulfate) and it helped immediately.

(https://www.vitamindcouncil.org/about-vitamin-d/am-i-getting...)