3(1)If the owner’s estate or interest is insufficient to enable the owner to grant the right for an indefinite period, the period for which the right subsists does not extend beyond the date when the owner’s estate or interest determines.
(2)If planning permission for the use of the protected site as a site for mobile homes has been granted in terms such that it will expire at the end of a specified period, the period for which the right subsists does not extend beyond the date when the planning permission expires.
(3)If before the end of a period determined by this paragraph there is a change in circumstances which allows a longer period, account is to be taken of that change.