Disable auto-start of postgres server on boot (Mac)

Running a Mac. I installed Postgresql 9 many years ago and configured it to auto-start. Now I have upgraded to version 12 using brew, but on system restart version 9 server is still starting automatically. I don't know how to determine what is starting it, I don't see anything in my bash_profile and I don't see a feature in brew or pg_ctl that allows me to disable an auto-start configuration. I have no postgres files in /Library/LaunchAgents either. Thanks