Answer of query no. 3 is modified- As per recent Circular No. 26 dated 29th December 2017, you can add ITC of September and October while filing the GSTR 3B return of November. click on the link to see the circular. Page No. 8 is relevant for this case: www.cbec.gov.in/resources//htdocs-cbec/gst/circularno-26-cgst.pdf