Consider extending security support for Alpine 3.13
Due to this issue since Alpine 3.14 it's mandatory to update docker to at least 20.10.0 for correct work of Alpine.
Because it's a significant upgrade and it takes a while to safely perform and test docker upgrade I suggest extending the security support for Alpine 3.13 (until Apr 2023?). There are still patch updates being released for Docker 20.10 and usually you want to have a very stable version of docker in production.