y, "now" can be used to set the completion date to the current
    time. To remove the completion date from a milestone, specify an empty
    string ("").

milestone due &lt;name&gt; &lt;due&gt;

    Set milestone due date

    The &lt;due&gt; date must be specified in the "YYYY-MM-DD" format. Alternatively,
    "now" can be used to set the due date to the current time. To remove the
    due date from a milestone, specify an empty string ("").

milestone list 

    Show milestones

milestone remove &lt;name