Debian 10 Buster became stable a few months ago, the rest of the systems had to follow but took their time. This is done every two years and creates a wave of confusion, especially those on forked versions of Debian, like antiX, MX, devuan, refracta, etc. Even more dangerous and confusing it is if you are using testing and although testing during debian stretch was buster it now becomes bullseye, while your antiX/MX/Devuan is testing alongside Buster still.
After antiX announced 19 (Marielle Franco) as its current stable branch, MS followed its mothership the week later (a few days ago), while Devuan/Refracta are still chasing Stretch (Debian 9), what they call Devuan 2 or ascii.
So here it is, to take the confusion away from numbers and names:
Debian * Debian * AntiX/MX * Devuan the last good1 * 7 Wheezy * 13 * 0 beta-testing old old stable * 8 Jessie * 15 * 1 jessie (old-stable) old stable * 9 Stretch * 17 * 2 ascii (stable) stable * 10 Buster * 19 * 3 beowulf(testing) testing * 11 Bullseye * 21 * 4 chimaera (next testing) unstable * sid * sid * ceres