Section 422.415 - Changes in open-end credit terms(1) Except as provided in sub. (2), no creditor shall make any change in the terms of open-end credit plans that is adverse to the interests of the customer with respect to any outstanding balances or that imposes or alters a charge permitted under s. 422.202(2m). For the purposes of this section, a change shall be presumed to be adverse if the result thereof is to increase the rate of the finance charge or the amount of the periodic payment due. Outstanding balances shall be determined on the assumption that all payments shall be credited first to any finance charges that may be due and then to the payment of debts in the order in which the entries to the account showing the debts were made.(2) A change that is adverse to the interests of the customer with respect to outstanding balances or that imposes or alters a charge permitted under s. 422.202(2m) may be made if any of the following conditions is met: (a) The change is required by legislation, regulations or administrative rules becoming effective after the date of the agreement with the customer and the creditor has mailed or delivered to the customer written notice disclosing such proposed change not less than 3 months prior to the effective date of such change or such lesser period of time as may be available before such change is required to be made.(b) The change is made within 3 months of March 1, 1973 or within 3 months after the repeal or expiration of any federal legislation, administrative order, rule, guideline or regulation, the purpose of which was to limit or freeze finance charges or other charges, in effect on March 1, 1973, whichever is later.(c) The creditor mails or otherwise delivers to the customer a written disclosure of the proposed change not less than 90 days prior to the effective date of such change.(d) The customer agrees in writing to a change other than a change made to apply a finance charge permitted by the treatment of s. 422.201(2) by chapter 168, laws of 1979, to a balance outstanding on April 6, 1980.(3) No term of a writing executed by the customer shall constitute authorization for a creditor to unilaterally make changes in the terms of the credit plan, which are otherwise prohibited by this section.(4) A violation of this section is subject to s. 425.304.1971 c. 239; 1979 c. 168; 1981 c. 45 s. 51; 1993 a. 150; 1995 a. 328.