Hello ! Yep I can see bananas on the F57 pictures and I'm not surprised as it happens frequently with Nirvana seeds since 2003 (as far as I can remember ). That mean your plant is a female dominant hermaphrodite which mean you have a low amount of bananas but still got some. If they did not opened then you are safe and you will not get seeds so you can remove them one by one carefully. If one already opened then it's not really sure you'll het seeds as the bananas cane late in flowering so the seeds will not have the time to be fully formed ( 4 weeks to get a perfect seeds ). Be careful and everything will be all right. I hope it will help you 😁✌️🏼