In our Canadian winters, the weather can often cause valid concerns about resin freezing. Sometimes it gets left on a front step, or a community mail box compartment, or in an unheated area at home (ie: garage), and can freeze. This is not ideal, however the resin can still be recovered and used.
The important thing, is to let the resin thaw & return to room temperature naturally. This may take a few days or more, depending on the size of the resin. You do not want to add heat to it at this time. If it's still frozen, and you try to prematurely thaw it with additional heat, you may be adding moisture to it, which will affect the resin. Allow it to thaw on it's own.
Resins will function as usual once allowed to thaw naturally.
Any resin can randomly crystallize and is difficult to predict why. some resins might end up with a bit of white type of crystallization at the bottom, if it's been frozen or stored too cold. If this occurs, and all the resin is thawed, try setting containers on a heated blanket, or in a hot water bath. After about 10-15 minutes, give the bottles a good shake to break up the crystalizing formed from freezing (or being too cold). You may need to repeat this many times, but continue until the white crystals break up into the resin. Once it's all broken up and blended again, it can be used as usual.
Once opened, ideally use any resin within 6 months. Store in a warm, dark, dry area preferably until used up.
Please Note: If you are concerned you may not be around at delivery time for your parcel, consider having resin delivered to a work address where it's warm, or maybe sign up for Canada Posts Flex Delivery. Then you can pick up your parcel at the post office location nearest you.