Yes, an inmate can be released from prison on a Saturday.
Inmates are usually let out during the week, but there is no rule that says they can’t be let out on the weekend. The exact date and time of an inmate’s release will depend on a number of things, such as the length of their sentence, any parole or probation conditions, and the rules of the prison where they are being held. If you have specific questions about an inmate’s release, you should contact the facility where they are being held.