at has no --help option. -h works.
Internal RFE bug #125949 entered.
If this gets fixed upstream, we will inherit it. Suggest pinging the upstream maintainer.
I can't submit this upstream because the author has no workable e-mail address.
Debian is considered upstream for "at" these days. So please contact the Debian maintainer: Ryan Murray <rmurray> and you may also want to report this problem in their tracking system <http://www.debian.org/Bugs/Reporting>.
Reported.