When I looked into it, /e/ constantly used to be many months late with security updates. LineageOS for microg and iodé were much quicker (~ 1 month max which is still not that great).

Hmm, possibly I'm looking in the wrong place, but as far as I can remember, I've been getting new /e/OS versions about every month, and looking at the release notes [1], they usually seem to include the latest "Android security patches", which I assume is what's relevant - unless there's something else that should also be included?

[1] https://gitlab.e.foundation/e/os/releases/-/releases