We've had plenty of carriers announce various dates for the upcoming Windows 10 Mobile update for existing Windows Phones devices. So far, Microsoft themselves have been pretty cagey, with all official indications remaining that the update will come sometime "early in 2016." The latest carrier to buck the trend, according to plaffo.com, is Vodafone Italy.
According to documents listed in a Vodafone Italy support page, the Italian carrier is set to push the update March 7-13, 2016. That's next week, for anyone without a calendar handy.
Again, Microsoft hasn't given any indication that an update is right around the corner, other than pushing a number of updates lately that bring release-ready Windows 10 Mobile updates ever closer. In the meantime, take this information with a grain of salt, and we'll keep our eyes out for more and better data.