I have never tried to accomplish this but I would guess it is not possible. If I were trying to get it done, I would brush up on the Page property and see if I could get the page numbers to Debug.print at specific key values. I would place VBA in the On Format event of a specific section of my report. Depending on what approach I took, I may be interested in the value of the On Page property, also.
https://msdn.microsoft.com/EN-US/lib.../ff195525.aspx
https://msdn.microsoft.com/EN-US/lib.../ff835059.aspx
From there, you would have to get the Printer and go after its properties. As far as I can tell, the Printers Collection is just under the Application layer. So I do not think you will have much success adjusting the printer while the report is being rendered. I have had enough trouble just trying to select a specific printer for a specific Reoport Object, let alone adjusting the printer properties on the fly. Maybe something like
Code:
Me.Printer.Orientation = acPRORLandscape
https://msdn.microsoft.com/EN-US/lib.../ff193183.aspx
https://msdn.microsoft.com/EN-US/lib.../ff198274.aspx
The only way is probably to print or export to PDF and then Automate Acrobat via Access.
I would probably render two reports, one in landscape and one in portrait. I would use info from the Report's Page Property or search for text in the PDF file after it was rendered. With the page numbers in hand, I would create a new PDF file using Acrobat Automation.