Karen- If Peter’s information is correct- and I have no reason to question it-then the harps with this problem would fall into that 2 year window. The harp I mentioned on my original post was bought by the Cunard line-I’m presuming they bought it brand new)- to put on the Queen Mary II. I believe that was 7 years ago. It’s possible the harp was built a year or more earlier and took that long to sell. I have not seen more recent instruments so don’t know if they have this rivet problem or not. But since I had seen it on a 7 year old instrument, I assumed it was on everything built since then. My mistake.