There is no vesting of fee rates under this section, except for properties included in Utility Local Improvement District (U.L.I.D.) No. 70-1. Properties in U.L.I.D. No. 1, which front upon existing sewer lines, are permitted one connection per lot in existence on March 1, 1970, or a number equal to the number of stubs assessed as part of U.L.I.D. No. 1 if greater than 1. If such property has been subdivided since March 1, 1970, then the vesting goes with the first lot developed, and only for the number of stubs assessed (minimum one). Additional units constructed, installed, or utilized as separate residences shall be charged at the current rate.