This rule might sound obvious, but still everyone doesn’t follow it. The key here is that if you have temperatures below zero degrees, a winter tyre will perform better than a summer tyre. If you add ice or snow, the answer is even more obvious.
The key is that the tyres that you use are approved for winter use. So even if you have all weather tyres on your vehicle and they are approved for winter use, you will be fine. If you don’t, then you shouldn’t be driving if you have any winter weather outside.