Shipwrecks Regenerated?!

Seed: -215776231942321378

Coordinates: 184 72 -904

Observed Result:

     When we first discover this area, we found a single shipwreck(Jungle Wood), and made that chunk loaded. Then we went to a far place, and returned after some minutes. When we went back to the shipwreck place, another shipwreck(Acacia Wood) appeared. The two shipwrecks both have chests with treasure maps, and led to two different treasure. The regenerated shipwreck(that Acacia one) can't be located with command. But the two treasure can both be located. That was so strange.

Please fix the bug.