I recommend using the term "overdraft fees" because that's how you have to label them in the periodic and YTD totals on statements (even though you could use "overdraft fees" there and something different everywhere else.
Truth in savings and Reg DD don't require the disclosure of daily fee caps. I think you could make a case to say it requires disclosing a de minimis overdraft for OD fees, though.
With the possible exception of the de minimis OD amount, neither Reg DD nor Reg E requires a change in terms notice for the changes you're describing.
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John S. Burnett
BankersOnline.com
Fighting for Compliance since 1976
Bankers' Threads User #8