In the case of such a membership which was last begun or last resumed prior to March twenty-ninth, nineteen hundred forty-four and which now is continuing pursuant to such paragraph four of subdivision c of section forty of this article, and so long as federal service of such member shall continue hereafter without interruption, the member shall make only the payments required by former section fifty-two-c of the civil service law, as amended by chapter seven hundred ninety-four of the laws of nineteen hundred thirty-nine. Federal service covered by such former section fifty-two-c of the civil service law shall not, for the purposes of this paragraph, be deemed to have been interrupted by the rendition of service to the state immediately after such federal service and the return to such federal service not later than four months after the termination of such service to the state.
N.Y. Retire. and Soc. Sec. Law § 42