When I first got my DCS-932L cameras the firmware was very basic. There were no schedule at all.
So I created my own, fairly rudimentary, program that had a schedule functionality. I had to create camera definition files by hand (textfile in a specific format) which looked like this
//Camera 1. This camera start motion detection each weekday at 7:30 and stops at 16:30. During weekdays
// detection mails will be sent to mymail@mymail.com. Mondays enable motion detection from
// midnight to 05:00 and will send those mails to myothermail@mymail.com
// Wednesdays enable motion detection from 16:30 to 20:00. Mails will be sent to the last address registered.
// Weekends have not been mentioned which means that the program will not make any changes to
// those days. If the camera motion detection is active it will remain so, if not then not.
Camera;192.168.0.2;admin;myPass
Info;Livingroom
Video;mjpeg.cgi
Schedule;Weekdays;7:30;Enable;mymail@mymail.com
Schedule;Weekdays;16:30;Disable
Schedule;Monday;00:00;Enable;myothermail@mymail.com
Schedule;Monday;05:00;Disable
Schedule;Wednesday;16:30;Enable;
Schedule;Wednesday;20:00;Disable;
Fairly simple, yet quite powerful in its own way. I could turn the motion detection on and off multiple time each day, and the program allowed me to load different camera files so I could basicly set up a number of different schedules in different files and load the one I needed currently. (but only one of those definition files running at a time). It required a computer to be up and running the program thought.
The program also had a couple of simple Turn motion detection on/off buttons.
So basicly exactly what you are looking for...
I made it for firmware version... oh... 1.5 I think it was... way back anyway... and I have not updated it since, so I don't think it will work with the current firmware.