Not quite what you're asking, but this was a comment I copied on long term food storage for just such an occasion. Don't remember the original author, I'm afraid.

If you have the space + money:

• Flour is much cheaper in bulk. 25 lbs is ~30-50% cheaper bought all at once rather then 5 lbs at a time.

• Storage is very important. I recommend a 5 gallon food grade bucket with a gamma lid. https://www.amazon.com/Gamma2-Seal-Lid-Combo-3pk/dp/B0CZW3QB79

• Pest control is important with bulk food storage. Things that help include putting bay leaves in the flour, using an oxygen-killing pack in with the flour before sealing it for the first time, and using a secondary container for ~3-5 libs at a time so that the storage container is opened infrequently.

For non-flour items, I recommend using the same strategy but for rice and beans. Rice can be kept free of pets by baking it at 150 for 30 minutes before storage. You can do the same for beans though the quality degrades a tiny bit (beans have fewer pests anyways).

1 bucket of each is enough food for 2 people for a couple months all by itself (plus a vitamin to avoid malnutrition). Not a bad way to buffer yourself from food price swings. If you get some bulk fat like a gallon of refined coconut oil or peanut butter, you'll have a ton more calories for cheap. I'd say the total cost for everything I just described is around $150-250 and would be enough calories for 2 people for 3ish months. Add some bulk spices and canned tomatoes and it could even taste good.

Also all of these tips work for mutual aid buys and storage if you have access to a kitchen.