sleepuntil is a mix of sleep(1) and at(1). It takes the same format of time as at(1), including "noon" or "teatime". Since it uses the parser from at, you can refer to the at man page for the format.
sleepuntil noon && sendmail something sleepuntil 5:00pm && sudo reboot
$ ./configure $ make $ sudo make install
Last updated: 2013-04-11