Except as provided in Section 211.3, the term “employment” shall include service performed after December 31, 1971, by an individual in the employ of a nonprofit organization. As used in this Act, the term “nonprofit organization” means a religious, charitable, educational, or other nonprofit organization defined in Section 501(c)(3) of the Internal Revenue Code of 1986 which is exempt from income tax under Section 501(a) of that Code, and which has or had in employment 4 or more individuals within each of 20 or more calendar weeks (but not necessarily simultaneously and irrespective of whether the same individuals are or were employed in each such week), whether or not such weeks are or were consecutive, within either the current or preceding calendar year (or which has elected, pursuant to Section 302, to be an employer); provided, that services performed for the organization are excluded from the definition of “employment” in the Federal Unemployment Tax Act solely by reason of Section 3306(c)(8) of that Act. An employing unit cannot be a nonprofit organization prior to 1972.