Nothing special or wrong going on there. Every 4 versions there is a Long Term Support (LTS) release. 1.27 is LTS, the next LTS will be 1.31, and so on.
See https://www.mediawiki.org/wiki/Version_lifecycle for more info, including exact months when versions reach EOL.
Ah! Gotcha. Thanks .. I guess that says something about me that I assumed there was something scandalous going on, lol.
-Rich