The freezers are in the heated main station, however since the "waste heat" from the generators is put to use it's not as inefficient a system as one might assume.
The comical part of the food storage situation is that the station was basically built without anywhere near enough of it. The main "dry store" is in a room on a different level from the kitchen, labelled "Science Storage", and most of the near-to-hand frozen stuff is on an outside loading deck near the galley.
I have no insights beyond what I read in the OP, but my point was that those freezers are actually warmer than outside. So "anywhere near enough" might in fact be enough if you can store deep-frozen things outside on the loading deck.
You only need enough freezer capacity to "warm up" the outside stuff to normal freezer temperatures (the article mentions this). This only depends on the warm up time, and number of people / consumption rate. Mission duration only impacts how much outdoor space is used.
My observation is based on spending over a year in that station, and being close with someone who was a chef there.
It really isn't as simple as those "only" statements. There are other uses for freezers than warming stuff up to normal freezer temperature. The on-station food storage situation is a real hack. Shoveling snow off boxes of food in your too-small outdoor deep-freeze doesn't need to be part of the chef's job. Reading red printing on those cardboard boxes, is rather difficult under the red light that tends to be preferred outside in winter.
