Regarding film expiration date, I happen to come across an interesting post on l-camera-forum not long ago:
http://www.l-camera-forum.com/leica...7-thoughts-10yo-frozen-tri-x.html#post2574245
"I was on the Ilford factory tour recently and the 'use by' dates came up in
the Q&A session.
As I recall even if film is unrefrigerated Ilford say under normal
conditions (not in the glove box of a hot car in the tropic's) film should
last fifteen years beyond the sell by date before anybody should worry. The
date is so dealers can turn around their stock efficiently. So a roll in the
desk drawer isn't going off, neither is the roll in your least loved camera
, unless you really hate it...
I don't like the idea of unused film regularly going in and out of the
fridge at the end of a days shooting simply because the idea of expansion
and contraction comes into my mind. And I've never re-refrigerated sheet
film because I worry about condensation forming inside the open packet, but
new and sealed it lives in the fridge."