Sec. 4. All leases for grazing purposes heretofore issued by the Commissioner of the General Land Office which are covered or partially covered by any easement or surface lease granted hereunder are hereby made subordinate to such easement or surface lease. If the lessee under any existing oil and gas lease heretofore granted by the State on any area affected by an easement or surface lease granted hereunder, shall file or cause to be filed in the General Land Office an agreement, subordinating to the easement or surface lease granted hereunder all rights held by such lessee under such oil and gas lease, then and in that event the running of both the primary and principal terms of such lease shall be suspended during the existence of such easement or lease; provided, however, that lessee continues the annual rental payment stipulated in the lease during such suspended period. Such oil and gas lease shall remain in status quo, and all obligations, duties, rights and privileges existing under such lease shall be inoperative and of no force and effect until the expiration of said easement or surface lease, at which time said oil and gas lease shall again become operative and all of the obligations, duties, rights and privileges, including the payment of rentals under same, shall again attach and be in force as they were on the date of the suspension and continue for the unexpired term of such lease. The School Land Board shall give notice immediately to such lessees that their leases are again in force when said easement or surface lease has terminated; provided, however, that the annual rental payments have been met.