The commentary to 1030.5 is what you have.
1. Form of notice. Institutions may provide a change-in-term notice on or with a periodic statement or in another mailing. If an institution provides notice through revised account disclosures, the changed term must be highlighted in some manner. For example, institutions may note that a particular fee has been changed (also specifying the new amount) or use an accompanying letter that refers to the changed term.
Appendix B-2 provides model language should you wish to use it.
B-2--Model Clauses for Change in Terms
On (date), the cost of (type of fee) will increase to $----.
On (date), the interest rate on your account will decrease to ----% with an annual percentage yield of ----%.
On (date), the minimum [daily balance/average daily balance] required to avoid imposition of a fee will increase to $----.
You are not required to post terms of every active account time online, nor should you. You have bigger UDAAP issues advertising account terms that are not currently available for new accounts on your website. Remember the purpose of the website is advertising under 1030.8, not providing disclosures under 1030.4. That is why Reg DD requires that you provide disclosures "in writing in a form the customer may keep." If a grandfathered customer has questions about their account, the regulation assumes they should be looking back to their account opening documents.
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