I've noticed that when an OPUS Share is submitted for a mark that had only Scaled horizontal coordinates, the data sheet is usually revised to show HH1 (mapping grade) coordinates that are a rounding to 2 decimal seconds of the OPUS coordinates.
But I looked at some of the OPUS Shares in my area and find four where the data sheet shows 0.01 to 0.05 seconds different from the share.?ÿ If there is more than one OPUS session, those agree to much better than that.
It really doesn't matter, since the coordinates are still plenty good to find the mark again and probably won't be used for much else, but it seems puzzling.?ÿ
The only explanation I can come up with is that somebody did enter HH1 coordinates from a mapping grade unit, and the system doesn't replace those even though OPUS is better.?ÿ But I can't imagine who entered them because there are no recovery reports in a likely date range.