I am a FO for a 121 carrier and I got an email from someone who keeps track of our medical dates. I am over 40 years old and this guy says that now that the rules have changed and I have to get a medical every 6 months. I have an ATP but as an FO I am only exercising the privileges of a commercial pilot, am I not?, and would only need a 2nd class. Am I correct in my thinking on this, I've been to faa.gov and I don't really see any new rules. Do I have to get a 1st class every 6 months?