W. Va. Code § 11-15B-22: Effective date of rate changes for certain services.

The effective date of rate changes for services covering a service period starting before and ending after the statutory effective date is as follows:

(1) For a rate increase, the new rate applies to the first billing period starting on or after the effective date.

(2) For a rate decrease, the new rate applies to bills rendered on or after the effective date.