The jobs are stored in subfolders of the Archive folder, each of these sub-folders has the form:
YYYY-MM-DD-XXXX, where the front part informs about the date when the sub-folder was created, while the number at the last part serves to sort sub-folders created in the same day.
In the subfolders, you can find two files for each of the printed, copied or scanned jobs:
a PDF file with the preview of the job
an XML file with basic information about the job, such as the type of the job or the username of the printing user.