BLUE TONGUE SKINKS

I've bought some Fluker's gourmet-style canned grasshoppers and mealworms for my BT but the cans have no best before date. It has an expiry date which is November 2015 but this has to only apply if I haven't opened them right? It says to keep the lid on and refrigerate after opening which I've done. I just don't want to end up giving him something that has gone a bit nasty.

Thanks in advance!

I have used canned insects and followed the storing guidelines. At best 1 to 2 weeks before I saw a science project. The expiry date is for unopened cans.