I do not have details about any mitigation. There are rumors that people have independently come across php2shell exploits.
I shut down my servers five hours ago. This might have seemed premature at the time.
I think the best course of advice for most people is to shut down their servers as soon as they possibly can.
I applied the mitigation to all my servers when it was released, but now I've stopped all the httpds. A few hours of overnight downtime, vs potentially trying to restore everything from backups tomorrow. Everyone should weigh it up.