Changing a Holiday Calendar or a Factory Calendar is not an activity that is generally done frequently. Once you have established what are the Statutory Holidays for a set Calendar, the only changes that happen are for the "Irregular Holidays", and these are usually created only once a year, if not less frequently.
As for creating new Periodic Work Schedules, this is usually only done when there is a requirement for a new schedule. In a Transport Company (such as a Bus or Airplane), this could happen frequently, but I don't think that it is a task that could be automated.
Have you tried to create a new schedule or modify a calendar?
Have you looked at the documentation on these processes (in help.sap.com or the Time Evaluation Wiki of this site) ?