There are two ways I can think of.
One is to have both set of layout pages in your template.
Once you start on a job and decide what size layout page you want simply delete the other.
The second is to use an 'Autotext reference'
Place a drawing on the last page of your layout set (or you can use an existing drawing).
I created a PDF file of some text that explains the process that I use and I place that as a drawing.
The advantage of this is that you move it to any page rather than using an existing drawing that you want on a specific page.
Select this drawing and right click to set it as an Autotext Reference.
To be continued...
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11