After not flying since 2008, I am finally going to be able to start again. My last 3rd class medical was issued in May 2007, shortly before the 3rd class medical was made valid for 60 months instead of 36 months for those of us under 40. Am I correct in assuming this is retroactive for medicals issued before the switch, and my medical is good until the end of May, 2012, and did not expire at the end of May 2010? A quick search of Part 61 didn't really help me determine an answer. I'd like to know for sure rather than assume.