A gist for issue "Datetime. Ranges: Unknowns, Opens, and Unspecifieds."

Gist-Biblatex-Ranges-Basic.tex

\documentclass{article}
\usepackage{a4wide}

\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
% Ranges
% ==========================================


% Unknown
@book{simpson_cool_book_0092,
  author = {Simpson, Lisa},
  title = {Cool Book 0092},
  date = {unknown/2006}, % EDTF
  timestamp = {2016-10-31T05:55:17Z}
}

@book{simpson_cool_book_0093,
  author = {Simpson, Lisa},
  date = {2004-06-01/unknown}, % EDTF
  title = {Cool Book 0093},
  timestamp = {2016-10-31T05:55:37Z}
}

@book{simpson_cool_book_0094,
  author = {Simpson, Lisa},
  title = {Cool Book 0094},
  date = {*/2006}, % WD ISO 8601-2
  timestamp = {2016-10-31T05:56:44Z}
}

@book{simpson_cool_book_0095,
  author = {Simpson, Lisa},
  date = {2004-06-01/*},  % WD ISO 8601-2
  title = {Cool Book 0095},
  timestamp = {2016-10-31T05:57:12Z}
}


% Open
@book{simpson_cool_book_0096,
  author = {Simpson, Lisa},
  date = {2004-01-01/open}, % EDTF
  title = {Cool Book 0096},
  timestamp = {2016-10-31T05:57:31Z}
}

@book{simpson_cool_book_0097,
  author = {Simpson, Lisa},
  date = {open/2004-01-01}, % EDTF
  title = {Cool Book 0097},
  timestamp = {2016-10-31T05:57:56Z}
}

@book{simpson_cool_book_0098,
  author = {Simpson, Lisa},
  date = {2004-01-01/}, % WD ISO 8601-2
  title = {Cool Book 0098},
  timestamp = {2016-10-31T05:58:30Z}
}

@book{simpson_cool_book_0099,
  author = {Simpson, Lisa},
  date = {/2004-01-01}, % WD ISO 8601-2
  title = {Cool Book 0099},
  timestamp = {2016-10-31T05:58:56Z}
}


% Unspecified
@book{simpson_cool_book_0110,
  author = {Simpson, Lisa},
  title = {Cool Book 0110},
  date = {199u},
  timestamp = {2016-10-29T10:31:01Z}
}

@book{simpson_cool_book_0120,
  author = {Simpson, Lisa},
  title = {Cool Book 0120},
  date = {19uu},
  timestamp = {2016-10-29T10:31:17Z}
}

@book{simpson_cool_book_0130,
  author = {Simpson, Lisa},
  title = {Cool Book 0130},
  date = {1999-uu},
  timestamp = {2016-10-29T10:31:33Z}
}

@book{simpson_cool_book_0140,
  author = {Simpson, Lisa},
  title = {Cool Book 0140},
  date = {1999-01-uu},
  timestamp = {2016-10-29T10:31:47Z}
}

@book{simpson_cool_book_0150,
  author = {Simpson, Lisa},
  title = {Cool Book 0150},
  date = {1999-uu-uu},
  timestamp = {2016-10-29T10:32:07Z}
}
\end{filecontents}

\usepackage[%
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % Dates and Datetimes
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % julian=true,% convert dates before gregorianstart to Julian Calendar
    % gregorianstart=1582-10-15,% Default
    alldates=ymd, % year, short, long, terse, comp, ymd, edtf. ymd = Year-Month-Day format
    labeldate=ymd, % year, short, long, terse, comp, ymd, edtf. ymd = Year-Month-Day format
    alldatesusetime=true, % print time components in non-compact date ranges
    labeldateusetime=false,
    alltimes=24h, % 12h, 24h, 24hcomp. 
    seconds=false, 
    timezones=true,
    datezeros=true,
    % dateera=astronomical (default), secular, christian
    %   astronomical dates, controlled by datezero
    %   secular (prints BCE/CE) controlled by dateerauto, datezeros
    %   christian prints BC/AD controlled by dateerauto, datezeros
    dateera=secular,
    dateeraauto=501, % Sets the max year ceiling for automatic printing of era
    abbreviate=true, % prints full localisation strings
    dateabbrev=false, % prints full date localisation strings
    dateuncertain=true,
    datecirca=true,
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % Style
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    style=authoryear,
    sorting=none,
    dashed=false,
    url=false,
    %refsection=section,
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % style=authoryear option
    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    % mergedate=  % false, minimum, basic, compact or true (default), maximum.
    %    See \doc\latex\biblatex\examples\50-style-authoryear-biber.pdf
    mergedate=false
]{biblatex}
\addbibresource{\jobname.bib}

% Space between table rows
%\renewcommand{\arraystretch}{1.5}

\begin{document}

Note \verb|sorting=none| is set.

\begin{refsection}
\section{Unknown}
\begin{tabular}{|p{180pt}|l|l|}
  \hline
  \textbf{Description} & \textbf{Input} & \textbf{In text citation result}\\
  \hline     
  Start date unknown, end date specified. ``Unknown". & \verb|unknown/2006| & \autocite{simpson_cool_book_0092}\\
  \hline     
  Start date specified, end date unknown. ``Unknown". & \verb|2004-06-01/unknown| & \autocite{simpson_cool_book_0093}\\
  \hline  
  Start date unknown, end date specified. ``*". & \verb|*/2006| & \autocite{simpson_cool_book_0094}\\
  \hline     
  Start date specified, end date unknown.``*". & \verb|2004-06-01/*| & \autocite{simpson_cool_book_0095}\\
  \hline    
  \noalign{\bigskip}  
\end{tabular}
\printbibliography
\end{refsection}

\begin{refsection}
  \section{Open}
  \begin{tabular}{|p{180pt}|l|l|}
    \hline
    \textbf{Description} & \textbf{Input} & \textbf{In text citation result}\\
    \hline           
    Start specified, no end date. ``open". & \verb|2004-01-01/open| & \autocite{simpson_cool_book_0096}\\
    \hline   
    No start date, end date specified. ``open". & \verb|open/2004-01-01| & \autocite{simpson_cool_book_0097}\\
    \hline 
    Start specified, no end date. [Nothing] & \verb|2004-01-01/| & \autocite{simpson_cool_book_0098}\\
    \hline   
    No start date, end date specified. [Nothing] & \verb|/2004-01-01| & \autocite{simpson_cool_book_0099}\\
    \hline                 
  \end{tabular}
  \printbibliography 
\end{refsection}

\clearpage
\begin{refsection}
  \section{Unspecified}
  \begin{tabular}{|l|p{120pt}|l|l|}
    \hline
    \multicolumn{2}{|l|}{\textbf{Description}} & \textbf{Input} & \textbf{In text citation result}\\
    \hline
    Within a decade. & Some unspedified year in the 1990s & 199u & \autocite{simpson_cool_book_0110}\\
    \hline    
    Within a century. & Some unspecified year in the 1900s. & 19uu & \autocite{simpson_cool_book_0120}\\
    \hline     
    Within a Year (to month level). & Some month in 1999. & 1999-uu & \autocite{simpson_cool_book_0130}\\
    \hline     
    Within in month. & Some day in January 1999. &  1999-01-uu & \autocite{simpson_cool_book_0140}\\
    \hline   
    Wtihin a Year (to day level). & Some day in 1999. &  1999-uu-uu & \autocite{simpson_cool_book_0150}\\
    \hline           
  \end{tabular} 
  \printbibliography[heading=subbibliography]
\end{refsection}

\end{document}