AVC threw a message at me on launch that version 1.9 was available. Both GitHub and SpaceDock show version 1.8 as the latest version.
HPTechTree.version lists 1.8, too. So not sure where this bug originates, but figured I’d let you know regardless.
KSP: 1.2.2 (Unix) - Unity: 5.4.0p4 - OS: Mac OS X 10.12.1