A family of Microsoft word processing software products for creating web, email, and print documents.
Hi
I don't know if you have sorted your problem out.
But I have an idea that might or might not work for you but, if you go to "print" on word then go to directly below "printer properties" there should be a button "page setup" click this then go to "paper" then on paper source there should be two columns "first page" and "other page" click to select "auto tray select" for both then go to the bottom left corner there is a button "set as default" click that then click "yes".
This should set all print you do to what ever tray or setting that you have done on "page setup".
I'm still not sure what your trying to do and I don't use word that much but this is what I know to fix the problem that similar to what you were talking about, but remember not all saved file will do this so you might have to set this up again and save the file this will save any setting and changes that you have done to that file. But all files for word 2013 and newer any changes or setting you do for this file should work for all other files you do on your computer.
Hope this helps