I dont really make edibles.
But i can say hash pills in coconut oil will store fine for atleast a year at room temp. If you need something thats stable in your car this time of year i cant really think of anything at the moment. Those candies are a good idea. And they are right. If youve ever smoked a blunt, i dont know why it most often happens with blunts and especially sativas, even brick weed.. but can make the tip of your tongue numb. Thats similar to what edibles do.
My 2 pennies