Good Evening,
It will not damage your module, it has a triac as the output device and this is electronic, not mechanical.
The cycling will degrade the life of the lamps but not by that much. The cold surge will not be as bad as the first cycle as the filament has not had time to fully cool.
Depending on what is on your network you have the possibility of flooding your network which would manifest itself in other portions behaving erratic.
My solution would be to go to the local dime store and purchase some lamp flashers. They simply drop into the socket, screw in a bulb and presto they flash at about your rate. A lamp adapter with a plug and a relay with a 115V (230V) coil would be very inexpensive. You could use a low voltage relay and a brick that would work as well. Mount the relay in a 4x4 metal electrical box with a single duplex cover. Use a box connector to bring in the two wires, one for the coil, the other to power the load. Hook the green wire to the box and the green screw on the duplex. Connect the white wire to the white screw an the black to the Common of the relay. The Normally Open contact is then connected to the brass screw on the duplex receptacle. If you want to get fancy break the bar between the two brass screws and connect the Normally Closed Contact to the other screw. The outlets will then alternate.
Have Fun
Gil Shultz