Yes, that was something I checked before writing my post here.
As you’ll see from @anon467281’s reply, this is probably what’s happened.
(Actually, he only wrote a Note as a way of seeing if his changes were getting back to me. But what you describe could be a real situation, so …)
… although it’s a little more techy, I’d say it’s pretty safe to close PT and copy his Notes XML file from his old project over the one in the correct project that he’s just received. Then re-open PT and do an S/R. I’d be interested in comment from @John+Wickberg, @anon848905 or someone else from the team as to whether there are any pitfalls here. I’m thinking it’s OK because S/R is used to seeing the Notes XML change on the computer of the owner of those Notes.
[What I’ve sometimes needed to do, but been more scared of doing, is to edit another user’s Notes file on my computer. I’ve always assumed that, if there’s a conflict, Mercurial will take the owner’s copy to be the right one, and wipe out my changes. But I could well be wrong: maybe to Mercurial there’s no concept of ownership – it’s just another file that two people have changed.]
Yes, there’s no better way to do that.