Where the Indenture or any Indenture Supplement provides for notice to Noteholders of any event, such notice shall be sufficiently given (unless otherwise herein expressly provided) if in writing and mailed by registered or certified mail or first class postage prepaid or national overnight courier service to each Noteholder affected by such event, at its address as it appears on the Note Register, not later than the latest date, and not earlier than the earliest date, prescribed for the giving of such notice. In any case where notice to Noteholders is given by mail, neither the failure to mail such notice, nor any defect in any notice so mailed, to any particular Noteholder shall affect the sufficiency of such notice with respect to other Noteholders, and any notice which is mailed in the manner herein provided shall conclusively be presumed to have been duly given.