Hi Patrik, I think you can choose October month from calendar as preset
"Last month" & September month by selecting all days using mouse drag.
Book-mark the report. By default, it should be set to monthly rolling.
Otherwise also, you can also schedule it to be sent (rolling monthly per
you requirement) using "Advanced Delivery Options", screenshot attached.
Try accessing book-marked report or the scheduled reports, it should
work for your case...Let me know if you see an issue.