Section 353 - Submission of estimates1. The head of each administrative unit shall submit annually to the budget officer on or before the first day of October, an estimate of revenues and expenditures of such administrative unit for the ensuing fiscal year. The budget officer annually may require that such estimates be so submitted on or before a specified earlier date, provided that in no event shall such estimates be required to be submitted prior to the first day of September. The estimate for each administrative unit shall be subdivided according to units of organization and shall show the source of revenues and shall itemize the character and object of expenditures. Estimates shall be submitted in such form and shall contain such additional information as the budget officer shall prescribe.2. The head of each authorized agency shall submit annually to the budget officer, on or before the date fixed by or pursuant to subdivision one of this section, a request for an appropriation for such authorized agency for the ensuing fiscal year. Requests shall be submitted in such form and shall contain such additional information as the budget officer shall prescribe.3. The budget officer annually shall notify the head of each administrative unit and authorized agency in writing of (a) the date fixed by or pursuant to subdivision one of this section on or before which the estimate of revenues and expenditures or request for an appropriation, as the case may be, must be submitted, and (b) the form of, and information to be contained in, such estimate or request. Such notice shall be given not less than twenty days prior to such date.4. In the event that the head of an administrative unit fails to submit an estimate by the date specified by or pursuant to subdivision one of this section, the budget officer forthwith shall prepare an estimate for such administrative unit.