Possibly it installed from the Russian Fedora repo, then. When I tried out Postinstallerf for Fedora 19, it installed an old version of flash, and not from the adobe repo.
Ahhh.. haaa.. Looking back through my yum history.. I found out what happened. I never told postinstallrf to install the flash plugin since I had already installed it from the adobe repo.. But, when you first run postinstallerf, it does an update... Since I had flash-plugin installed, it updated it, but with an older version.
Updated flash-plugin-220.127.116.117-release.x86_64 @adobe-linux-x86_64
Update 7:18.104.22.1680-1.R.x86_64 @russianfedora-nonfree-updates
It appears the Russian Fedora people stuck an epoch on there which makes yum think it's a more recent version.