just put a crop of sour d in jars a few days ago with the same problem, bananas in the last couple of weeks of flower, with ideal conditions. from what i've read, selfing is just in the sour d's nature.
i pluck- you've got a day or two before that banana opens up to a swollen flower- and let 'er run until ten weeks and have had nothing but compliments.....
gave one guy an anxiety attack, it's so fierce.
i tried reverse and penetrator on half the last run, once a week before flowering and once a week after, and the whole crop had the same issues...still no seeds, though.
when you see the first male flower, you have about ten days until you cut, from my experience.