By which I mean, how long could you reasonably bug-in without ANY retail food shopping. *
<1 month ?
>3 months ?
>6 months ?
>12 Months ?
*Maybe you expect limited shopping would still be viable.
Do you even agree about the value of storing extra food?
What are the strengths and weaknesses of your extended pantry?
I'll start
>6 Months of austerity level sustenance for two, with some obvious compromises such as having to substitute canned foods, crackers and corned beef for the more regular diet
Strengths :
Cheap.

Plenty of cleaning products and toiletries.
Some comfort foods and ample variety.
Aligned to (my) regular diet.
Weaknesses :
Cheap.

Some of the food would not be popular with MrJJ
Lots of Value range cans and produce.
Stock rotation has been neglected, so lots of cans past BBE.
Reliant on Freezers. First line reserves.
Currently Short on Flour, sugar and dairy.
Weak in sustainability. Few seeds and little growing/foraging/hunting skills.
Weak on cooking facilities.
Not very accessible.