Complex sentence: Its creation raised Ontario's number of public holidays to nine per year, but, as it is not recognized in the federal sphere, all federal employees (such as public servants and postal workers) still work on this day (or take vacation).
Split into simpler sentences: Its creation raised Ontario's number of public holidays to nine per year. However, since it is not recognized at the Federal level, all Federal employees (such as public servants and postal workers) still work on this day (or take vacation).