My employment status changed mid-year from that of being an independent contractor to that of being an employee. Form 2210 keeps causing the rejection of my e-Filing and it says it's rejected because of the lack of an "explanation statement." I have provided that "explanation statement" within the form and it still is being rejected (over 5 times now). My W-2 withholding for the last two quarters exceeds what my estimated tax payments were supposed to be. So, I have overpaid and no actual underpayment condition exists. Why does the IRS or TurboTax not seem to either transmit or recognize the included "Explanation Statement?" It's very frustrating!