https://www.endpoint.com/blog/2014/05/19/git-checkout-at-specific-date
git checkout `git rev-list -1 --before="Jan 17 2020" HEAD`
You only need a little change if you hit the limit of reflog (the date you cloned the repo or 90 days a go of history it seems from other notes)
git checkout `git rev-list -1 --before="Jan 17 2020" HEAD`
And you can also use
git checkout `git rev-list -1 --before="Jan 17 2020 8:06 UTC-8" HEAD`
it will checkout the previous commit related to the date or the date-time you enter, see that you can use modifiers for the date, I guess if you dont use UTC+-N it just uses UTC time.