Use the Configure Time Periods page to specify the time periods used for activity searching. Setting time periods for your enterprise enables you to track not only who is accessing your sensitive applications, but when they are doing it. Access at unusual times might indicate a security issue that requires investigation. Time periods include things such as office hours, holidays, and weekends. Each time period is set individually so that you can customize the setting to meet the needs of your enterprise.
There are four types of time periods:
Is there any way to read these time periods from a rule?
Don't worry I came right, this seems to work:
context.getObjectByName(TimePeriod.class, "holidays");