No change in the rate of tax imposed by LMC 3.52.050 shall apply to business activities occurring before the effective date of the change and, except for a change in the tax rate authorized by RCW 35.21.870, no change in the rate of the tax may take effect sooner than 60 days following the enactment of the ordinance establishing the change. The designated official shall send to each affected business at the address of record a copy of any ordinance changing the rate of tax promptly upon its enactment. [Ord. 253 § 1, 2000; Ord. 215 § 1, 1999.]