575. If a municipal corporation has imposed in 1979 a tax or a permit under a provision that ceases to have effect on 1 January 1980, and the tax or permit has been imposed for a period ending in 1980, the municipal corporation must refund to every person who has paid the tax or the permit for the whole period, an amount of it proportionate to the relation between the number of months of that period in 1980 and the total number of months of that period.
The refund may be replaced by an equivalent credit on the business tax payable by that person for the fiscal period 1980.