We are switching to a different new accounts platform and are redoing all terms and conditions. Trying to understand the 30-day rule, if we send new T&C to all accounts that state the day of implementation, are we able to start using the new platform right away as these new account will be getting the new T&C? Or do we have to wait until the 30-day period is done?

What terms are changing when you switch?

Not changing any terms, but the wording with this new platform is different.

The terms and conditions is a legal document, not a compliance document. Since there is no Reg DD change in terms that does not require a change in terms. However, if you are changing your deposit contract, then any notice requirements would be based on the terms of the previous contract and applicable state law and you should be asking your legal counsel to review if you are not sure of the requirements.