Answer: a tax preparation office
The office that experiences the bulk of their work especially on Month of April is the tax preparation office. 'Tax Season' is the time period between January 1 and April 15, in which individuals traditionally prepare the previous year's financial statements and reports. In the United States, the filing of annual tax return should be done by April 15.
A tax preparation office receives these forms/statements in bulk and needs them to be processed within this period also, thus Braedon’s employer required them to work ten-hour days starting April 10th.