The first two weeks of April are projected to be the busiest of the year for the IRS, and for good reason! There's normally a big rush of people who are trying to get their taxes done, right before the deadline.
I wonder how holidays will affect it, because April 15th is Easter. Are people going to try to get taxes done right before Easter? Or will they use the three-day Easter weekend to do their taxes? Not everyone is getting a three-day weekend, though.
I do know that Saint Patrick's Day was slower than normal at the IRS, because it was on a Friday this year. Pretty much everywhere was slow that day; people want to spend their Friday holiday partying, not working. People joked that we'd get a lot of drunk taxpayers at the call center on Saint Patrick's day, and...well, I can't say if we did or not! That would be breaking privacy rules!
(But seriously, don't do your taxes while drunk. Drunk math is usually bad math. As they say in algebra class, don't drink and derive.)