ATE,
I agree with TTE that in this case the visa status has no bearing on whether the individual is a resident for U.S. tax purposes under the substantial presence test.
With regard to the start of the residency, Treas. Reg. 301.7701(b)-4(a) provides in part:
An alien individual who was not a United States resident during the preceding calendar year and who is a United States resident for the current year will begin to be a resident for tax purposes on the alien's residency starting date. The residency starting date for an alien who meets the substantial presence test is the first day during the calendar year on which the individual is present in the United States.
With regard to the termination of the residency, Treas. Reg. 301.7701(b)-4(b)(1) provides in part:
An alien individual who is a United States resident during the current year but who is not a United States resident at any time during the following calendar year will cease to be a resident for tax purposes on the individual's residency termination date. Generally, the residency termination date will be the last day of the calendar year.
Thus, unless an exception applies, Kevin would be treated as a resident of the U.S. until the last day of the calendar year.
Treas. Reg. 301.7701(b)-4(b)(1) provides in part:
[T]he residency termination date for an alien individual who meets the substantial presence test is the last day during the calendar year that the individual is physically present in the United States if the individual establishes that, for the remainder of the calendar year, the individual's tax home was in a foreign country and he or she maintained a closer connection (within the meaning of §301.7701(b)-2(d)) to that foreign country than to the United States
This exception to the general residency termination rule would not apply to Kevin because he was present in the U.S. on the last day of the calendar year. I can find no other exceptions that would apply. Thus, Kevin's residency starting date would be January 1 and he would have no residency termination date (he was a resident through the end of the year).
There is no need to write to the IRS on this issue. The statute and regulations are clear. Kevin is not a dual status taxpayer for 2008. He is a U.S. tax resident for the full year.