This is called the climax cause something surprising happened.
Answer: I am writing to request permission for time off to be with my father for a day on January 1st. I will be held up because He wants to go see fireworks for new years. I will be done with my father in one week and I promise to get back to work immediately I am done.
Explanation:
An author's purpose is the reason that he or she is writing a piece; whether it's narrative, persuasive, expository, or informative.