Hello student, hope you are doing good.

So, to answer your question, the colleges in Maharashtra and mumbai in general, are not likely to reopen anytime soon before diwali. Initially it was decided by Union Education Ministry by the issued guidelines for the States to reopen the schools and colleges from October 15, but in view of current scenario of the state and India as in whole, the situations have gotten worse and it will not be appropriate to physically conduct classes . Therefore, you need to wait till diwali to know about any further notice for reopening of colleges .

Hope this helps you. Good Luck !!