Freeze well. I usually mix a handful with savory spices (turmeric, black pepper, etc) into yogurt. Or maybe with just some oregano?
Mash the blueberries up a bit and put them in a jar, do not overfill. A coffee filter may be necessary to keep bugs and what out. After a few days, the mixture should be slightly fizzy. If not, it may need yeast or some other starter to help get things going.
Some houses may be too sterile. Fresh blueberries still with the yeast on them may help? Natural fermentation can be pretty hit or miss, especially if you do not do a lot of it, and do not live near where the blueberry bushes are.
Mix water, cornstarch, thyme, lemon powder, mix well. Heat to boil, add blueberries, and cook down for a bit on lower heat. You can start this before other dishes and leave it on a simmer and then finish it off when close to serving.
The original recipe recommended 1/4 cup sugar, but, really? Blueberries are already sweet enough.
The thyme stood out, probably need to use less, or to balance it out with something. Cardamon, maybe?