The average emulsion can be stored as a gelled material at about 3 deg C for nearly a year or more. With a better preservative against bug attacks it can be extended to about 2 years or so. Fog growth can be inhibited by TAI at the proper level.
Also, the emulsions that I have been making are so repeatable that I am now blending mixes, so I can make 400 g this month and two months from now, down to 200 g, I can make another 400 g, mix them and have 600 g of good stuff. I see no reason why the slower emulsions of any sort that I have read on-line could not be blended in this fashion.