i ask who complained, they keep telling me no one, and that they found out by doing their friday patrols for sign violations. every time i get a letter, it's a new person in that role. so my guess is that as they hire a new enforcer, they get out and try to enforce the code.
one time i prodded a little more and asked what they could actually do to me, and she said pretty much nothing, unless i failed to comply for a long time, they could take me to court. seems like a waste of tax dollars to get someone to take down signs which are drawing in business, producing tax revenue, etc..
don't get me wrong, i still put signs up for promotions and such, but mostly on the weekends only.