Sir,
Actually there is no post of Administrator in Govt. Aided High school, all schools are run by the Managing Committee, but if due to some exceptional causes ( may be irregularity or any other crisis) the MC dissolves then from WBBSE appoints any Govt Official (e.g. S.I. or A.I. of Schools) as the administrator of the School. In this case DI of school generally propose the name of officer to WBBSE to appoint as Adminitrator till MC forms in the school. Thankin you.