Replace Motion Graphics Template in Timeline
Say you created a template for a Lower Third and put in all text and data necessary. But your client does not like the layout. It would be handy to create another template and replace the old templates in your PR timeline. And your text stays the same!
(Just like you could in FCP7 with Motion3...)
As of Pr 12.1 / Ae 15.1 Ae mogrts that have been used in a Pr sequence can be replaced with a new version of the template by alt/opt dragging an updated version onto an existing aegraphic in your sequence. You can choose to have the template updated everywhere it was used in the project or restrict the change to that one instance. Where possible, Premiere Pro preserves your customizations.
https://helpx.adobe.com/premiere-pro/using/whats-new.html#april-121 --> Replace clip workflow for Motion Graphics templates