I don’t think anyone is up to anything nefarious, I’m just not comfortable giving out the exact coordinates of a location that I visit regularly. I also don’t publish my account name on my submissions. (I can tell you that if you know the general area, you can place it on the satellite map just from the photos. If I wanted to falsify a location, that would be a very poor choice.)
I didn’t particularly do a deep dive, but I found several other topics describing a problem which sounds basically the same, or at least like it could have been the same thing, just from using the related posts that showed up at the bottom of the screen.
In a couple of those posts there are other people talking about having had the same experience with the location moving after they reopen a draft. So, it may not have been officially documented as a bug, but it’s been reported, and the behavior appears not to be unexpected. This is why I posted in the bug report forum rather than the general one.
If I had known that the location might be changed when I reopened the draft, I would have double checked it. That needs to either be treated like a bug, and then fixed, or else there should be a notification warning you to check the location when you reopen a draft.