Probably no-one knows for sure, although I agree it would be nice to know!
Based on what happens with other things, it could go either way. Extreme cold either kills things, or preserves them. Humidity level could also make a difference--some things die when they get too dry, others last a long time when dry but die if they get humid and moldy.
If I think as a gardener-- dry and cold is good for most seeds, and keeps them viable for a very long time; but the warmer they are, and the more moist they are, the faster they "die." After the seed has grown into a plant, too cold or too dry will kill it, while warm and moist is generally good.
Some kinds of fish live shorter lives in warm water, longer lives in colder water, because their metabolism speeds up or slows down according to the temperature (so they die of "old age" in a different number of years: for guppies the range is something like 3 months at 100 degrees, 5 years at 70 degrees.)
Of course a virus isn't exactly the same as a seed or a plant or a fish, and it's not even exactly the same as another virus, so we're stuck with the experiments that have been run, plus guessing.
But I wouldn't be confident guessing either way, whether the cold makes the virus live a shorter or longer time.