@DrOct @Ron Yep, Stephen nailed it. Every post available via the public archive should work fine but the internal archive in the Posts tab of your settings is broken in the way you have reported, Ron.

For now, the workaround is to use the public archive to get your links. You can still search in your internal archive and then match the post to the public archive. Hopefully you'll only need to do this for the short term.

I'm gonna tag @manton just in case but I'll also log this on GitHub.