I only used june stats so this is slightly off, but if Ubers was usage based:



Ferrothorn, Ditto, Magearna, Smeargle and Mega-Diance would be banned from OU (if you used 1760 stats Drill, Blissey and Cloyster would be too)



OUBL would be ~33 mons (I might have messed up counting and I stopped looking through the list once I saw the last Arceus forme)