TimePasscode Pro cydia tweak allows you to set the current passcode to the current device’s time.
Other features include the ability to set an offset (positive or negative), and display the time on the passcode screen.
For example, if the current time is 1:50, then your passcode would be set to be 0150. If you have a time offset of 15, then the passcode would be 0205. If the negative offset switch is enabled, then it will subtract minutes rather than add, making your passcode 0135.
Military time is supported. The format of the passcode (12-hour vs 24 hour) is determined off of your device’s Date & Time settings.