If you search back, there are several threads here on the keeping properties of films in the fridge or deep freeze, and on the use of films after their expiry date.
You can retain films for processing for some time (say, a few weeks) after exposure if this is necessary, but, in general, just process as soon as you can to avoid any risk of deterioration.
Personally, I have no concerns in using film well past its expiry date when I've kept it frozen unexposed from new, but, once exposed, I either process it myself or send it to the lab as soon as possible.
(Any particular reason why are you keeping the films unprocessed? :confused: )