I give up, I can't be expected to help if you change the setup, call Xerox, speak to 2nd level support.
"Unless i missunderstood something about the Define Media for Pages(s), this would work if i have a small job but if my pdf file is 2000 pages does that mean i have to list every page in the Define Media for Page(s) separated by comma"
"Thanks for the prompt response Joe.
Say I have 4 page pdf file."
If you have a 2000 page job and want a printer to insert anything you have to define where and when, if you want to print on different media you have to define where and when, or trust Adobe to get it right via their software via "Choose paper source by PDF page size", but that won't work well with stock types, only sizes.
You really thought I would come here and ask how to print 2 pages with two tabs!! Anyhow, I'm at a walking distance from Xerox headoffice. I will give them a visit tomorrow and post the solution here for others to benefit from.