ORIGINAL: Old Fart
I hav'nt read whether you are using single pack or 2k.If it's 2k and you've sealed the jar well and put it in the fridge it may last a day or so,after that it's toast.
I'm not sure what "single pack or 2k" is. I'm using 2 part paint and reducer. I've got it vaccum sealed in a mason jar in my cabinet. It's only about 4 oz. so if it's done gone bad it's no loss.