I am talking about the sealing rubber but it doesn't look like what you describe, and what I read about in the Island forum. So far as I can tell, my Revolutions don't have a "U" part to fit over a narrow rim of the hatch opening. There is only an "O" attached with some adhesive to a fairly wide lip of the hatch opening. On one of the boats, parts of the "O" were still attached, but there was no "U" part doing the attaching, at least not one that I could see.
We've only done one excursion since the super glue fix. If it fails in the near future, I'll report back.