This should work without subreports. Though to answer your question; there is no way to rotate a subreport 90 or 270 degrees.
For main report, the orientation is controlled by section. So somehow, you will need to figure out which section will start on page 3, then format that section to print Landscape. There is no way to actually tell the report; when you get to page 3 print Landscape. This is because the report does not know how much data or how many objects can be fit on page 1 and 2.
- Ludek