Debian: How to mirror a minor version that is not the current one

I use Debians apt-mirror to create a local mirror. Here's the entry in /etc/apt/mirror.list for getting lastest Debian 11 - that is 11.7. deb http://ftp.at.debian.org/debian bullseye main What to do when I need a specific minor version (e.g. 11.1) of bookworm? How can I get this with apt-mirror or otherwise?