This is BLFS-BOOK version r12.0-1685 dated February 28th, 2024. This is the svn branch of the BLFS book, currently targeting the LFS development book. For development versions, if this version is older than a month, it's likely that your mirror hasn't been synchronized recently and a newer version is probably available for download or viewing. Check one of the mirror sites at https://www.linuxfromscratch.org/mirrors.html for an updated version.