The latest stable version of Evolution can be downloaded from Softpedia
Evolution 3.12.4, a complete solution that provides integrated mail, address book, and calendaring functionality to users of the GNOME desktop environment, has been officially released.The fourth maintenance build of the GNOME 3.12.x branch has been launched and comes with quite a few changes. It's surprising to see so many improvements in just a maintenance update, but this is actually a very good thing.
According to the changelog, the next message is now selected after move, the text column now expands with the recent GTK+, the local machine's domain in Message IDs is no longer used, the automatic “mark as seen” feature is no longer cancelled incorrectly, a crash that occurred on the calendar Copy has been fixed, some crashes that occurred when trying to load images in e-mails have been corrected, the recursive inline-PGP-signed text is now shown properly, and Google Tasks support has been added.
Also, the Send/Receive dialog now closes on errors properly, excessive CPU usage due to GtkSpinner has been fixed, automatically marking message now works properly, multiple folder selection is now allowed, and a few other fixes have been implemented.
A complete list of bug fixes can be found in the official changelog. You can download Evolution 3.12.4 sources right now from Softpedia.