Dog needs to learn to swim past the 1st gunner, so if dog beaches early because it is lost then you handle to teach dog the 2 down the shore concept. Here you are teaching dog where to look for the mark.
Or if dog beaches early because it is cheating, then you handle to teach it not to.
The question is whether dog should get reprimanded. If it is cheating, yes, if it is lost, no.
I would not intentionally let my dog return to an old fall, or beach early.