The best way to do this is to make the tray you want the AS400 to pull from tray number 1 directly on the printer. You can do this on most printers through the printers front panel or their web interface.
Otherwise you can change the print file for each report (CHGPRTF) and change the “Source drawer”.
Your software should indicate which tray to pull from. Most of our printers are IBM, which work fine. However, HP printers will not pull for the correct tray unless you have the device configuration configured correctly. The key is the Manufacturer type and model. Refer to the IBM Software Technical Document # 21800146:
I’m pretty sure that even if it is configured correctly it will want to pull from the drawer that is configured on the printer as drawer 1 unless the print file says otherwise. These is nothing on the print device or OUTQ to specify which drawer.