[ant hill]

That's a good question as I go though cartridges of 300Ml as any insulin is spoiled by light, Heat, And air and they say if kept in the dark and at temps that will go off sae 50 - 70F you may have that for maybe a week or more and maybe work effectively but once out of the fridge and getting used then I would use it up wile you are using it as quickly from the fridge.
I would be suspicious if the stock is out of the fridge or in the light for too long as it may be off.
I hear that in the US that mail order people who handle insulins the wrong way as I get mine from a pharmacy. I find that mail order is no wiser to what they deliver as they may have the insulin in a hot van although some are waking up the fact that this is perishable item.