How far past "expired" will a resin tank still work?

Chances are you already have read this one but here we go: Pouring resin out to extend tank lifetime? - #20 by billb

After having to clean two Form 2s after a resin spill I’m not taking any chances yet on a broken Form 3 tank, so I’m swapping them when they expire. Your accomplishment is motivating to push the boundaries of the tank’s lifetime though…