(1) Where the personal debtor satisfies the creditor to whom a blanket mortgage is owed, or where, in a blanket mortgage, the claim and debt are merged in one person, then if the debtor is entitled to demand compensation only from the owner of one of the plots of land or from a predecessor in title of the owner, the mortgage on this plot of land devolves to the debtor; the mortgage on the remaining plots of land is extinguished.
(2) Where only partial compensation is payable to the debtor, and for this reason the mortgage devolves to the debtor only for a partial amount, the owner is to allow this amount to be counted towards the part of the remaining amount of the blanket mortgage to which the owner is entitled in accordance with section 1172.