This behavior seems new to me, or maybe I just recently enabled updates on my server. (??) I'm running a nightly of the Windows EXE that I downloaded on May 1. It's shown as:

Squeezebox Server Version: 7.9.1 - 1493198727 @ Wed Apr 26 09:34:16 CUT 2017

And today I saw a notification in the web interface of a new version that had been downloaded. Is this new? I thought notifications were only done for release versions.