I've been finding that every time I get in a boat and travel far enough that the location I got into said boat is out of simulation distance, the boat teleports back to that location. I did some testing and found that anytime I leave a boat, it teleports back to where I got into it and then quickly warps directly towards me, but if it teleports to unloaded chunks, it won't warp, leaving me with no boat until I leave and rejoin the game.
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We're tracking this issue in MCPE-125388, so this ticket is being resolved and linked as a duplicate.
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