It looks like it might be but it’s difficult to tell. I have had growths like that that weren’t “nanners” that I originally thought were and it turned out to be a bleached sugar leaf in my case.
https://www.growweedeasy.com/cannabis-plant-problems/male-plants-hermies-bananas
How is your airflow? If your air isn’t bringing in enough fresh CO2 for the plant to keep up with high powered lighting then the plant will yellow out and bleach.
My next guess would be temperature from the lights causing stress but you appear to have finished grows with this setup before, correct? So perhaps it’s just this strain not liking your lighting.