MariaDB 11.8.7 vs 11.8.7b release tags?

Hi,

I see on GitHub that there is one commit tagged mariadb-11.8.7
(https://github.com/MariaDB/server/commit/e7d1202da30b7707185dc9b55af4693d1e3e4f60)
and one mariadb-11.8.7b
(https://github.com/MariaDB/server/commit/b067340c34cb9cd481cace18717f6afc66226209).

What is this 'b' tagging scheme? What does the 'b' stand for?

If the 11.8.7 release was faulty and already went out in an
irreversible way that it could no longer be pulled and retagged, why
call the new release 'b' and not just 11.8.8?

Any automatic system looking at new release tags will likely only see
the mariadb-11.8.7 tag and disregard anything deviates from the
expected pattern, such as mariadb-11.8.7~alpha or mariadb-11.8.7-beta
or in this base mariadb-11.8.7b. Also for humans the meaning on 11.8.8
is very clear and would not prompt anyone to ask on the mailing list
what the 7b version is.