updating all lower third text in the same project at one time

Convert your graphic to a source graphic. Any changes you make to it will then update everywhere it's used.

1. Select the graphic in the Timeline.
2. Choose Graphics and Titles > Upgrade to Source Graphic.

This creates a version of the graphic in the Project panel. Add that source graphic to all your other timelines. Any changes will then update automatically.

Hi Mike — you can still get that “edit once, update everywhere” behavior by keeping the lower third in its own sequence and nesting it:

1. Put the lower third graphic in its own sequence.

2. Place that sequence into your main timeline everywhere the lower third appears, rather than separate copies of the graphic.

3. When the text changes each week, open the source sequence and edit the text there once. Per Adobe's documentation, any change you make to the source sequence automatically updates in all its nested instances.

One note from the docs: the duration of the nested clips stays the same, so if new text needs more time, extend the nested clips afterwards.

Reference: https://helpx.adobe.com/premiere/desktop/edit-projects/edit-nested-sequences/about-nested-sequences.html