The GSTR 1 for the month of August should be available at the portal from 1st Nov. And in case you've not filed GSTR 1 for the month of July, you should be able to file it from 1st Nov with late fee
@ Aman Agarwal yes, that's the confusion now becoz GSTR2 date has been extended. So there is no clarity if we can file GSTR1 on 1st November onwards or wait for another month.
Govt should have opened the window for GSTR1 also for couple of days.
The period for filing GSTR 1 for any month is ascertained to be from 1st to 10th every month. So, in my opinion, we would be able to file GSTR 1 for the month of August from 1st November.