I trust your opinion alot MagoMan. I dont see anything relatve in the nute and trouble shooting pages and i'm starting to think that its a strain specific trait. Its as if the stems on the fan leaves are turning red.
That is actually a small sign of purpling, this is normal for many types of mj plants to do this. Purpling could be a charactoristic of certain strains or from cooler temps. I don't believe you should have any worries about it.
Deffinately not a hemp strain...Tottaly different flowering characteristics. Hemp reaches for the sky pretty much throughout its whole growth cycle, and color change in hemp is rare, from what Ive been taught and seen anyway. Its a beautiful sativa though might I say, the skinny sativa leaves do resemble hemp though.