Student printing from laptops to any campus printer

Your university has 30,000 students and 150 printers across 20 buildings. A student sends a document from a laptop or phone, then walks to any printer and taps their student card to print it. Each page costs 10 cents from the student's print balance.

Students send about 40,000 jobs a day, 3 MB each on average. Up to 4,000 arrive in the 10 minutes before classes start on the hour. A job that is not printed within 24 hours is deleted. Each printer has a card reader and can fetch files from a server on the campus network.

At the end of every job, the printer reports how many pages it printed. If it jams or runs out of paper partway through, that count covers only the pages that came out. Students must never pay for pages that did not print.

Where does a job wait until the student taps their card, and what happens from the tap to the last page?