At my school, everything is done by hand. Preference is until 10 pm, with bid lists and the amount of bid cards for whatever quota is due to the Greek Advisor's office by midnight. The next morning, bid matching is done, and bid cards are addressed by the advisor who sits for each sorority during bid matching.
Rho Chis call any PNM in their group who did not get a bid and offers the option of any snap bids if possible, but there is almost never any of those. The PNMs are told if they don't receive a call by like 3 pm to come to the Student Union at 7 pm for bid distribution. The women come into the ballroom of the union and pick up their card, at which time they find out where they are going, and the sororities pick up their new members. It's a lot of chaos basically, but good chaos
Then each sorority does bid day/night as they see fit.