In the cases referred to in Cl. 10-10 the insurer may demand an additional premium in proportion to the time by which the insurance has been extended.
If, at the expiry of the insurance period, it is uncertain whether a claim for total loss will be brought under Cl. 11-2, sub-clause 2, Cl. 11-7 or Cl. 15-11, and the vessel is subsequently salvaged or reported safe, an additional premium may only be demanded from the time the assured, or someone acting on his behalf, gained control of the vessel.