The seam opened rather than the rubber tearing. Different problem?

Something has come apart on a top of mine and I do not think it is a tear in the usual sense. The rubber itself is not damaged at all. What has happened is that the join has opened up along the side, so there are two clean edges that used to be stuck together and now are not.

It happened while I was taking it off, and there was no dramatic moment, it just gave.

Is this the same repair as a tear or a different one? And is it a sign the piece is on its way out, or is a seam letting go just something that happens?