(a) A creditor unilaterally may amend a revolving credit account.
(b) A change made under Subsection (a) that relates to an existing or future balance of a revolving credit account and that is adverse to the customer may not take effect before the first billing cycle that begins after the 90th day after the date of written notice of the change to the customer unless the amendment is made under Section 303.103.
(c) With respect to a revolving credit account secured by an interest in real property, a creditor who makes a change under Subsection (a) that relates to an existing or future balance of the account and that is adverse to the customer must comply with the procedures in Section 303.103.