Old fashioned phone trees can be really useful IMHO OP. We used them when I worked in a school. If there was winter weather, you'd call say, everyone with a last name from A to G in the staff directory, someone else calls G to K, and so on and so forth.

You can combine the phone tree with literal runners -- so basically, someone takes their burner and calls suburbs A,B,C and D and then the runners go out and pass the word about the protest or action.