Readback January 2017 Issue
Reader Feedback: January 2017
This gets into how these various Advisory Circulars are updated. Once an AC is issued, it’s assigned a number and a version letter, such as AC 00-45G, Aviation Weather Services. That version can be revised by issuing changes. So, the full specification of the most recent document is AC 00-45G, Change 2. The main document—original version—is what is returned by the various searches; you’ve got to dig just a bit further to find the changed versions.