D.I. on salary account of teachers

Now the school teachers are very busy with the task of filling up of COSA forms. H.M.s have hard time too. I have come to know that D.I. of Barrackpore has instructed to maintain the salary accounts of all the teachers of a school at one branch of a bank. Many teachers of a school have their salary accounts opened either with different banks or at different branches of a particular bank. They have already submitted the COSA by furnishing their existing account details. In ECS mode of transfer it is not mandatory to open salary account of all the employees of an office with one branch! In my govt. office, the employees have their salary accounts at different banks/ branches for years!
Whether there is any G.O. issued from the Education Directorate/ Finance Ministry in regard to the compulsion of opening salary accounts of all the employees of an office at one branch only? What about the views of other D.I.s?