I have just tested this on a T3 and I think you do not need the flags.

Assigning previous on the Home Button of both of the lighting pages will take you back to the control of your source. If you are on page 2 of the lighting, you will have to press it twice: the first press will take you back to lighting page 1 and the second back to the source control.

I am not sure but I think the "previous" problem happens with 3 pages or more.