/sys$common/syshlp/helplib.hlb DCL Tips, Date Time, Delta  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Delta time is an offset from the current time to a time in the
    future. Delta time has the following format:

         "+[dddd-][hh:mm:ss.cc]"

    You can truncate delta time after the hour field. You can also
    omit any of the fields after the hour field format as long as you
    specify the punctuation marks.