12 days of food is a very tight fit.  It helps that at this stage in my life my caloric needs aren’t very demanding. I typically take 1,800 kcals per day on a 10 day trip and have to force myself eat the first 3-4 days.
By day 9 or 10 I start to get a bit hungry at bedtime.  I also typically lose 5-8 lbs so with an additional 2 days from my usual trips, I’ll lose a bit more and be somewhat hungry at the end.
I may just eat what I feel like the first few days and save the extra for the last few.  For comparison I eat 1,200 kcals – give or take – in my daily life and workout and walk 40-50 miles a week which maintains my 170lbs. It’s been the only real plus to an aging metabolism. I get those 1,800 backpacking kcals in just under 16oz per day and it’s basically the same stuff I eat at home.  High fats and proteins with complex carbs.
I will also be going stove-less which is my typical choice at home.  A big salad is my normal dinner which will be replaced with a protein bar and cold soaked carbs for dinner. I am not fussy when it comes to food and have adopted a “food is fuel” mentality in my life.
On the PCT many years ago, I did a couple of resupplies at gas stations and it was pretty much candy for a week each time.  It worked but I couldn’t go there again.  In fact, other than a little dark chocolate, I don’t bring any simple sugars on trips anymore.
