Seeds forming on multiple strains.

To start, I grew in the past, long story short, I got out of the hobby once I almost got caught. Fast forward a few years, I'm helping a friend grow, he's not that knowledgeable. From my experience, I never had any males, and only one ever went hermie, however, what he's got going on is entirely new to me.

Four entirely different strains, grown from seeds procured from a major online seedbank that I had used in the past to great success, are producing seeds, and not just one or two here and there, from what I can see, all four are covered. I searched and saw zero evidence of any bananas, although his grow space is cramped and hard to move around in, which means I couldn't do a thorough inspection. But you'd figure that you'd see atleast a couple bananas here and there with the sheer amount of seeds. A week ago when I last looked at it, there was no evidence that there were any seeds.

To my knowledge, the only thing he's changed recently was adding a T5HO to the underside of the plants, and he did mention that the light was on at odd hours. His 1000w HPS is running on 220v with a timer that fits the 220v plug, the T5HO was on a 110v with a different timer. He said that he only had put the light in a week ago, while the plants were on their fourth week of flowering (9 week flowering plants). I dont see how that could cause them to both hermie and produce seeds to that degree in a week's time.

Thoughts, ideas, anything?

 

To my knowledge there is no one growing around him. But technically, wouldn't outdoor plants still be vegging (in the U.S.)? I already thought it could be outside contamination, but I just couldn't see there being any local indoor grows nearby, atleast not close enough to fully pollinate 4 different strains.