Lens profiles missing since last update

Recently (I think since the last update) most lens profiles have vanished from Lightroom - currently I see only about 14 lenses listed in the Lens Corrections tab. If I look in the installation directory under Resources\LensProfiles\1.0 the set of lenses I see in the UI matches what's installed and is indeed very much smaller than I would have expected and doesn't match what's on the web site (https://helpx.adobe.com/camera-raw/kb/supported-lenses.html). 

I'm using 2015.10.1 build 1117303, I tried uninstalling and reinstalling Lightroom but to no effect.