Long but important:

Reconsideration of Rejected Budgets.

(a) If the budget is not approved in accordance with 603 CMR 41.05(2), the regional school committee shall have 30 days from the date of disapproval to reconsider, amend, and adopt a revised budget. With the approval of the Commissioner, this 30-day period may be extended an additional 15 days. Where the local appropriating authority is town meeting and the annual town meeting is dissolved prior to voting on the budget, the budget shall be deemed disapproved by that member as of the date of such dissolution.
(b) The revised budget adopted by the regional school committee and the assessments corresponding to such budget may be less than, equal to, or greater than the amounts in the previously adopted budget.
(c) Within seven days following the regional school committee's adoption of a revised budget, the treasurer of the regional school district shall calculate and certify the assessment of each member and shall transmit the assessments and a copy of the revised budget to the members. Each member's local appropriating authority shall have 45 days from the date of the regional school committee's vote to meet and consider the revised budget.
(d) The approval of a revised budget shall be as set forth in 603 CMR 41.05(2)(a) and (b). If a local appropriating authority of a member does not vote on the revised budget within the 45-day period and previously appropriated funds for its assessment in an amount greater than or equal to its assessment under the revised budget, that member shall be deemed to have approved the revised budget.
(f) In a regional school district comprised of two members, if the revised budget is not approved by the local appropriating authorities of both members, the regional school committee shall again reconsider, amend, and adopt a revised budget and shall convene a district-wide meeting in accordance with M.G.L. c. 71, § 16B, at which the revised budget shall be placed before all voters eligible to vote at said meeting. If a majority of voters at this district-wide meeting votes to approve the revised budget, such vote shall constitute approval. If a majority of voters at this district-wide meeting votes to approve a greater or lesser amount for the budget, such amount shall be placed before the regional school committee. If the regional school committee by a two-thirds vote of the full committee ratifies such amount, it shall constitute approval. If the regional school committee rejects such amount, it shall again reconsider, amend, and adopt a revised budget and shall reconvene a district-wide meeting pursuant to the provisions of this section 603 CMR 41.05(3)(f).
(g) A district-wide meeting convened in accordance with 603 CMR 41.05(3)(f) shall only consider budgets based on the statutory assessment method.
(h) A regional school committee may reconsider, amend, and adopt a revised budget at any time prior to the approval of a previously adopted budget.
(i) If a local appropriating authority votes to approve an adopted budget subsequent to the required date for such action but prior to the regional school committee's revision of the budget, such vote shall be deemed valid.
(j) Whenever a member's assessment is reduced to a lesser amount than previously appropriated by the local appropriating authority, that appropriation shall automatically be reduced to the lesser amount.

Establishment of Budgets by the Commissioner.

(a) If the annual budget for a regional school district has not been approved by July 1, the superintendent of schools shall notify the Commissioner, and the Commissioner shall establish an interim monthly budget for the regional school district. The interim monthly budget shall be one-twelfth of the regional school district's budget for the prior fiscal year or such higher amount as the Commissioner may determine. The interim monthly budget shall remain in effect until a budget is approved pursuant to 603 CMR 41.05(3) or December 1, whichever comes earlier.
(b) If a regional school district's budget has not been approved by December 1 of the fiscal year, the Commissioner shall assume fiscal operation of the regional school district pursuant to M.G.L. c. 71, § 16B and shall establish the final budget for the fiscal year. In this event, the Commissioner shall exercise fiscal oversight of the regional school district as provided in 603 CMR 41.07.
(c) Whenever the Commissioner establishes an interim or final budget for a regional school district under the provisions of this section 603 CMR 41.05(4), the treasurer of the regional school district shall calculate and certify to the members their respective assessments based on the statutory assessment method and using the final or most recently proposed state aid amounts, general fund revenues, and required local contributions for the budget year. Each member shall pay its respective assessment in accordance with the payment schedule in the regional agreement. The appropriation of funds to pay an assessment ordered by the Commissioner under this section 603 CMR 41.05(4) shall not be deemed approval by the member of the district's budget.