The rate of rent payable in money by an occupancy-tenant in any other district may, during the currency of a settlement on the application of the landlord to a Revenue-officer, be enhanced, subject to any rules made under this Act for the local area in which the holding is situate and for the time being in force :
     Provided that.--
         (a) an appiication under this section shall not be entertained when, within the ten years immediately preceding the application, the rent of the holding has been fixed at any settlement or under any provision of the other provisions of this Act, except those of sections 13,14 or 15, or a suit or application to enhance it has been dismissed on the merits ; and
         (b) no order shall be made on any such application which is inconsistent with any contract made after the current settlement and still in force, such contract being consistent with this Act.