(a) If the parties to a substitution agreement under Section 274.101 intentionally fail to send the required notice under Section 274.103, the substitution of the fiduciary is ineffective.
(b) If the parties unintentionally fail to send the required notice, the substitution of the fiduciary is not impaired.

(c) If a substitution of a fiduciary is ineffective because of a defect in the required notice, any action taken by a subsidiary trust company before the substitution is determined to be ineffective is valid if the action would have been valid if performed by the affiliated bank.