Try signing out from the Creative cloud and sign back in.Check if them you are able to see the updates in the Lightroom
Also are you using Ma cor windows
Update Creative Cloud desktop itself. It should sync with your installed apps much better in future.
No avail. I signed out of CC, I uninstalled all of my CC apps and reinstalled CC by downloading from website. Still the same. Yesterday I installed CC on my laptop and I immediately got 2015.3 there. I am running Windows 10 on both machines.I must say that I am 'combining' my private CC Photography subscription and a installation from school which is Indesign CC and Illustrator CC. This is not an installation by Adobe user name. I don't know how this interferes with each other. I made a screenshot with the 2 apps showing their helpmenu with the updates grayed out. I erased my account