When printing to old fashioned paper the new onCourse interface doesn’t make it very obvious where to choose a different paper tray. That’s because we use Chromium as the browser engine and it doesn’t understand about different printer capabilities.

The trick is to download the report by clicking the little download icon in the top right. Then you can open it with Acrobat or OSX Preview and access all your printer options. Or set up the same printer on your system twice; once with the normal printer tray and again with the alternative.