The district shall send to the board of directors of the East End district notice of a hearing regarding an improvement project or service that is to be financed with assessments under this chapter. The district shall send the notice by certified mail, return receipt requested, or by another method determined by the board to provide adequate proof that the notice was timely mailed, not later than the 30th day before the date of the hearing. The notice must contain the information required by § 375.115(b), Local Government Code.