For purposes of making determinations under this section, the Teachers’ Pension System and the Teachers’ Retirement System shall be considered together as one State system. For fiscal year 2026, each county government shall pay to the Board of Trustees on or before January 1, 2026, the amount specified for that county government under § 21–304(b)(6) of this subtitle. Beginning in fiscal year 2027, each county government shall pay to the Board of Trustees on or before each September 1 the amount specified for that county government under § 21–304(b)(6) of this subtitle. The Secretary of the Board of Trustees may allow a grace period not to exceed 10 calendar days for payment of the amounts certified under this section. If a county government does not pay the amounts required under this section within the time required, on notification by the Secretary of the Board of Trustees that a delinquency exists, the State Comptroller immediately shall: exercise the right of setoff against any money due or coming due to the delinquent county government; and pay to the Board of Trustees the delinquent amounts, including interest on the delinquent amounts at a rate of 7.75% a year, withheld in accordance with this paragraph. On receipt of the payments from each county government or the State Comptroller, the Board of Trustees shall credit the amounts received to the accumulation funds of the Teachers’ Pension System and the Teachers’ Retirement System.