Tex. Water Code § 55.360

Assessments imposed under Section 55.354(a) not paid when due shall become delinquent on the first day of the month following the date payment is due, and the board shall keep posted in a public place in the district a correct list of all delinquent assessments. If a person who owes an assessment has executed a note and contract as provided in Section 55.358, the person may not be placed on the delinquent list until after the maturity of the note and contract.