I collected 7 planks in 29 days, I think more is impossible. Would that be enough for a raft? On the 30th day, the hurricane came.
Another time, on the 11th day, pirates found the bottle. What bad luck..
However, there was also a time when a large ship found it on the second day and I was saved.
Oh, and the game cheats on fishing. Sometimes it shifts the whole line to the left or right to make it even more difficult to guess the correct numbers.