When you apply recent template revisions to a meeting, all of the regions that are already in the meeting are updated to include the recent revisions.
What about new regions?
Any new regions that have been added to the template as a result of the recent revision will not be added a meeting by clicking the "Apply Revisions" button. You need to add each of the regions to the meeting. Follow the instructions to add a region to a meeting to add the new region(s).
The new regions will be automatically included in meetings created after the template revision. You will not need to add the regions to those meetings.