There’s a longer thread about it here: Bug: Date edits revert to 1969-12-31 (+/- a day depending on time zone)
Updating to 1.26.1 partially fixes this though. There’s still a lingering issue where some previously edited dates, while stored correctly, will display a year of 1900. It’s only affected a small amount of my media. But enough that it’s still annoying as I have to edit the date to something else, save it, then edit it back in order to refresh both the complete date and the display year.
