It depends on the parking restrictions of the lot. Your parking transaction will continue until you have reached the maximum time limit for which you have paid, just like a meter.
Parking can be purchased by the hour for up to four hours at most lots with the exception of meters located in housing areas. Meter enforcement hours are as follows:
Housing areas: 24 / 7
Monday - Thursday: 7 am - 6:30 pm
Friday: 7 am - 5 pm.