From what I've learned, it's best not to age in the tin, unless you're specifically in the business of aging tins.

Even when perfectly packaged and sealed, tins are far more fragile than jars, where seal is concerned. There's no way for us to know the condition of a seal. Also, the baccy needs a "jolt" of fresh air, after sitting in a tin, stewing in it's own juice. That air helps a) evacuate stale air, trapped at packaging, and b) allows a final, minor fermentation. That's where flavors truly begin to marry and real complexity and nuance happen.

JMHO