11DSS is an alternative-universe script series, started in 2010 by The Silence Academy. 2 series' have been posted with a third series set to be posted in June 2013.
11DSS, follows the normal Whoniverse timeline up until the last few moments of The End of Time. David Tennant's Doctor regenerates into an 11th Doctor portrayed by Ewan McGregor, rather than the 11th Doctor portrayed by current TV-Series Doctor Matt Smith.
It was announced in 2013 by the 11DSS Executive Producer and Creator - The Silence Academy, that 11DSS will be ending by Christmas 2013 in it's fourth series. It is likely that Series Three and Series Four will air almost back-to-back, however this is yet to have been confirmed.