DPDT Toggle switch and Arduino timer

It's just written as "Shield" instead of Relay Shield.

Ah I should have clarified that as well. Digital Pins 4, 5 6 and 7 on the arduino control each of the 4 relays on the relay shield.

(More information here: Relay Shield | Seeed Studio Wiki )

Yes COM 4 is the command channel for one of the relays. NO is "Normally Open".

Yes the automatic on-off in the arduino works fine. It just cycles continuously.