If you're bugging in for sure man, you can go so utterly simple it's stupid. Just about anything shelf stable at ALL lasts in a nice quiet cool basement. I shop at the Asian markets because they live surrounded by ocean, and their food stales very fast. They also don't use much BPA in their cans (opting for cheaper steel cans that survive rough ocean crossings better) and most of their dry goods come packed with oxygen absorbers and all that. Add a kitty litter bin and there you go- long term storage. I have opened cans 3 years past best by date to find nothing but delicious ready made pasta waiting for me. Then, you have the way they make those MRE's in the first place. They are horrible, I'll tell you from first hand experience with the later ones. Reminds me of gas station food. They are basically treated with steam or pressure in such a way as to disinfect them, then quickly sealed away in Mylar with a vacuum. Full of preservatives and flavor salts too.
Now, you have to realize those food products are mainly reliant on a vacuum. Nothing living can exist in a vacuum. And on the other side of that coin, most grocery stores don't care to lose food either and stock stuff that last a pretty frigging long time. I go with one of the first ever wartime foods developed- spam. I am begging to experiment with it and gotta say I ate way worse in high school. Stuff keeps like polished marble tiles. Smoked fish keeps for damn near ever, too. Hard tack, which is easy to make was what pulled us through the revolution. Bannock mix is great to vac seal because it keeps for way longer that way than most mre's and can be made from acorns or anything for free. If you take those loose plastic bags of generic beans straight from the store and seal them up tight with a vacuum sealer, they last like 5x longer and stay free of pests. Even your favorite cereals, tightly vac sealed will keep for at least 4-5x longer than normal. I'll put it this way (I like good food a lot) would you rather eat some generic high school tasting fake enchilada that hits like a brick and odd shaped and compact, or start your day with your own custom meal that cost you 70% less and still keep your comfort foods like pre-made brownies (yes brownies!) maybe a snickers bar instead, some bannock mix, dried apricots, container of powdered milk? Sounds better to me than [TUNA MAC FOOD WITH CHEESE, MEAL READY TO EAT] jesus ::cringe::
I should do you a video on it, they last just as long. I have lived on MRE's and I am telling you I'll take fresh rat before I'll take another mre. MRE = meals refused by Ethiopians.
Me I see people wrestle with obtaining mre meals and to me, I checked them out for about ten seconds having ate them and put my thoughts elsewhere. Morale can work with you or against you, and food like that is doing half the enemy's work for them I swear to gawd.

If that's the way you want to go I'd say get the better sounding ones. I have ate some I wondered how in the hell I choked that down. Seriously, there have been Ethiopians who the troops give them out, and they go sell it to a traveler instead of eat it. They're expensive, too.
You can also set aside dried meats and fruits dude- I done plenty of figs from my plantation five years ago that are still sitting pretty today in just the pantry.

Dehydrator and good sealer will pay for themselves by the end of your first years supply. Dinty moore is another brand that comes to mind who makes some stable stuff. There's tales of ppl opening cans in 1967 that were from the war and they were still good. It's out there, just have to step back and think outside the box.