Vasari Corridor is open only to large groups through outside agencies
Yep, it seems that restoration on the Vasari corridor still has not even started but it is not generally open as a rule to the public, only to large groups of a certain size for which they will then open the corridor for that specific tour.
Your best bet is to look online for agencies that organize them, since they put the groups together to do the tours... they do tend to be on the pricey side, since it is not your general museum and needs the special opening.
The Uffizi museum office sometimes will also do their own tours which tend to be a bit cheaper but these are announced almost when they are about to start and are done only in Italian. If we hear of these, we'll let you all know by posting on our blog!