MJB
If you are getting Box A and Box C, I assume you are paying estimated taxes. If you are paying variable estimated taxes, you need all pages of Form 2210 as well as Schedule AI of Form 2210.
If you are making 4 equal estimated taxes, and have a refund, then you don't need to fill out Form 2210, and some of the tricks people are mentioning to remove 2210 may be in order.
Form 2210 (ALL of Form 2210) needed to be filed in my tax situation.
