If it was TEOTWAWKI or a grid down catastrophic disaster making fresh cheese is still possible even if you don’t have access to fresh milk as long as you have stored some dry powdered milk.
Some people say its even tasty. As with most things fat makes everything taste better, so if you have whole milk powder your cheese will have a richer taste. Unfortunately, almost all milk stored long term is the non-fat kind as the milk fats cause the powdered milk to go rancid very quickly.
My suggestion would be whole milk from the LDS centers found across america or online. They are stored in #10 cans for years and years of storage.
Picture Credit: tacticalintelligence.net