Here is some reading about Heraclitus

I agree with Heraclitus's philosophy about the material world. It is in constant change. He also says everything moves and nothing is at rest. Heraclitus concluded that you could NOT step into the same river twice.
The idea is this: since the composition of the river changes from one moment to the next, it is not the same river for any length of time at all. Everything is like a river in this respect. That is, nothing retains its identity for any time at all.
(taken from here )

Negative is right, if you accept this point of view, then neither ship is the T.S. However, according to the ancient Jewish way of thinking they both are the T.S. It just depends on which view you accept. If none, then Negative is right again. There is no solution because there isn't a standard agreement on where to draw the line. Which is what I think, there is no solution.