Because it's been announced on the PBS tumblr and Twitter; also Netflix, Apple TV, Roku, and mobile devices.
PBS is giving its viewership the gift of Sherlock s3. For free. Stream the 2014 episodes up through 25-Sept-2014.
The Empty Hearse
The Sign of Three
His Last Vow
So if you haven't seen the eps yet, or your friend hasn't, or your country hasn't got it yet -- go now! And what better way to celebrate Team Sherlock's big Emmy win than a rewatch?
To celebrate #Sherlock's amazing seven #Emmy awards, @pbs is streaming series 3 online for the next 30 days: http://t.co/roDkP6DeVj
— cumberbatchforum (@cumberbatchfrm) August 27, 2014