On a mac, you can uninstall the current package - then navigate to ~/Library/Application Support/Plex Media Server/ under your home directory. Here you’ll see previously installed versions. Once uninstalled, you can then install the version you wish.
For Windows users, check out this post: I need to rollback from the latest Plex update
@jebrossard currently the guide is still updating and refreshing for me. I have “enhanced guide” turned off and so far still have 2wks of guide data appearing. From the sounds of it, I may eventually lose this - at which point… back to the drawing board!
This would be so much simpler if Plex just got their act together with this feature…