It looks like the URL would be along the lines of:
http://camera-ip/decoder_control.cgi?co ... d=password
The SDK at http://www.foscam.es/descarga/ipcam_cgi_sdk.pdf has the different command #'s for telling it to go to different presets. Preset #1 is 31, preset #2 is command 33, etc. (it goes up by 2 for each preset since there's a set and a get for each one).
It should just be a regular http GET. Earlier posts in this thread mention using similar GET commands to trigger the motion alert, as a reference.
I guess a program to execute that at a certain time of day... I'm honestly new enough at really tinkering with my ISY that I don't know how to get a program to do that. I have a simple program to turn my porch lights on/off depending on the sunset/sunrise times, and one to trigger a set of lights when a motion sensor is activated, but that's all I've done really.
I was actually searching on here for something similar, although for my Foscam cameras, I use Blue Iris, so I need a way for the ISY to trigger that software package to start recording, like when one of my Insteon motion sensors triggers, or maybe have it trigger recording when a certain light switch goes from off to on. But since that's a software package, I guess I'll have to root around in their documentation for a way to trigger that from some command.