Wow that nuts...
Before you put your winters on, did you drive on your summers in extreme cold weather?
I need someone to confirm this, but: As for storage, temperature shouldn't make a difference (someone please correct me if I'm wrong). As long as there's nothing stacked on them, no movement, friction, and aren't mounted on a rim, etc... And they are allowed to slowly heat back up gradually (no flash freezing or heating), storage temps shouldn't make a difference. Keep in mind product is moved across the country in the back of semi trailers (majority not under temperature control) every day.
The tires should be covered under warranty, especially if they have good tread left and don't show signs of wear/usage. While rare, tires do have the occasional defects... Believe it or not back 4 years ago, on 4 new tires I purchased, 3 were defective. Warranty process was a bitch, but they were covered once proof/pics/test sheets were sent to the manufacturer.
Definitely wouldn't drive on them (even if you don't want to try and get them replaced). The last thing you need is a tire blow-out while doing 120-130 on a trip to Banff or Okotoks or something.
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