If a client called me today about whether or not to pay property tax in 2017, and it was one of my clients that can actually itemize, I'd tell them I'd probably pay it now if there is uncertainty about the benefit in deducting it next year. And there are always uncertainties about next year. A bird in the hand is worth two in the bush. Plus I have been around long enough to know that they are calling me because they want me to tell them to pay it now.
I realize I'm lucky as our property taxes are low, and I only deal with AMT once in a blue moon.
As far as taking it upon myself to call THEM and give advice? No. Not even if the law is changed tomorrow. I can't think about everything for 350 families. It is what it is.
I got amused yesterday at a local pro who posted on FaceBook that it looked like he and his wife would get a tax cut, but some people with kids would not. He does a lot of unnecessary talking. I don't know what he hoped to accomplish there, but nobody congratulated him, and immediately people started asking, "What about me?" After two or three replies of, "It's too early to say for sure," he removed the post. Um...