What is "Job Build"?
C9800 MFP has a function called "Job Build".
By enabling "Job Build", the MFP can construct a single copy job or scan job from multiple individual sheets.
You can scan a sheet from ADF and several pages from the flat-bed and combine them into a single copy job.
However, you cannot mix different sizes of original documents. When "Auto" is selected as [Original Size], the paper size will be determined by the first paper size.
You can not "job-build" with a sheet of A4 for the first page and a sheet of A3 for the second page.