Where the strict application of the schedule of hours, provided for by this section, imposes an unnecessary hardship and violates the intent and purpose of this act, the Secretary of Labor and Industry, with the approval of the Industrial Board, may make, alter, amend, and repeal general rules and regulations prescribing variations from said schedule of hours: Provided, That if it should be held hereafter by the courts of this Commonwealth that the power herein sought to be granted to the Secretary of Labor and Industry is, for any reason, invalid, such holding shall not be taken in any case to affect or impair the remaining provisions of this section.
43 P.S. § 103