They’re still encased in polymer. “Soluboard printed circuit boards need to be immersed in 90°C water (close to boiling point) for 30 minutes for the product to delaminate”, according to the CEO. I don’t imagine it will just melt/degrade slowly in a very short time span simply because of environmental heat and humidity.
This is just gesticulation ahead of the Camp David summit on August 18, involving the US, South Korea, and Japan; and the military drills involving the same countries the following week.