Grassland Archipelago is the expected spawn area, or possibly the Main Biome for Fishing Tycoon Unbound. It may be the hub island consisting of shops and minor areas. This area is confirmed to be in the game and is undergoing development.
As to the outskirts of the island, it remains in question as to if this will connect to other islands, or if you will have to travel by sea.
The island also has a small inlet in which boats possibly may go, as well as two docks, presumably for spawning boats.