VMS Help LIBRARY, /SINCE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Specifies that only those modules inserted later than a
    particular time be listed.

    Format

      /SINCE[=time]

 time

    Limits the modules to be listed to those inserted in the library
    since a specified time.

    You can specify an absolute time or a combination of absolute and
    delta times. For details about specifying times, see the OpenVMS
    DCL Dictionary.

1 - Example

  $ LIBRARY/HELP/LIST/SINCE=:12 ERRMSG

      This LIBRARY command displays information about help modules
      added to ERRMSG.HLB since noon today.