old cans are better because the oil  penetrates the fish.

let them seat in the reserve , and return the cans every month, helps the oil to penetrate the fish, and eat them only just before the last date. you'll have very good sardines, especially if olive oil

here in France we dont have a lot of factorys that stay in activity too, most of the cans come now from morrocco because the fishing place have moved to this area