Notwithstanding any other provision of this subchapter, no individual (other than a child described in section 1382c(a)(1)(B)(ii) of this title ) shall be considered an eligible individual for purposes of this subchapter for any month during all of which such individual is outside the United States (and no person shall be considered the eligible spouse of an individual for purposes of this subchapter with respect to any month during all of which such person is outside the United States). For purposes of the preceding sentence, after an individual has been outside the United States for any period of 30 consecutive days, he shall be treated as remaining outside the United States until he has been in the United States for a period of 30 consecutive days.