It is highly unlikely that your boat is going to fall apart because the epoxy has overheated in the sun and softened to the point it will no longer hold the boat together. There are hundreds of thousands, maybe millions of WEST system built boats around the world and a well built timber/epoxy boat is probably one of the most durable forms of boat construction. Much higher temperatures are required to soften epoxy. I did have personal experience of this quite a few years ago where I needed to do an emergency radiator repair on one of my cars. So, in what I thought at the time was a flash of brilliance, I made the repair with regular epoxy glue, only to find on my first longer drive in the car that the epoxy had softened and my repair had failed. But there are of course special high heat epoxy repair kits available.
