Website sometimes disapires from search results
Do you think it really didappears, or is it burried somewhere on 100th page of results?
I am sure. And it is after I changed ranking settings. Every refresh I see website in the first place appear and disappear
Yes, I see the page order as time-inconsistent in my case as well. After several refreshes it seems to still somehow.
If there is a bug, you can test the exact behavior to examine, where it could lay. At least to describe it, if there is not anybody keen to find-and-fix it now, later can be.