Duo is going to be my Hogwarts AU from Sorting Hat, because why not? He's a Gryffindor Beater, but a trouble maker with a lot of detentions under his belt. His parents, like Harry's, were killed in the first coming of Voldemort, though much less personally targeted. They were just casualties of the fighting. He was raised by a family friend, who was a priest, and then went to Hogwart's at 11 when he got his letter. The priest knew about the wizarding world. Also, this means he won't remember Marina at all.
Tieria is earlier in canon. Instead of being from near the end of the movie, he's now shortly before the final battle in season 2. His difference is that he decided to take Regene's and Ribbons' offer and join the A-LAWS. The catch is that he's doing it partially under cover. His motives were two-fold. He wants to get Veda back, but he doesn't want to abandon Celestial Being, so he's pulling a double agent act. He's figured out Wang Liu Mei's situation, and has recruited Regene to his side. The three of them have been feeding information on the A-LAWS and Innovades back to Celestial Being. He and Regene have also been working on a way to keep Ribbons out of their heads and close off a portion to Veda for themselves to continue their double agent work while trying to hide it from Ribbons. Their efforts have started to confuse the supercomputer, and things are coming to a head as Veda has been slowly cutting off more and more of Ribbons' access in favor of the other two. This also means he won't remember Marina, so this should be interesting.
Piper is from a canon-AU where Paige never came into their lives. Cole went back in time, and made it so that Paige had been unable to save herself from her adopted parents' car wreck and died with them. Piper has taken up the mantle of revenge against Shax for Prue's death, has not married Leo, and has no kids. She's much darker and angrier in this version, making her quicker to use her powers against others. She also wears a lot more black leather. Expect a wardrobe change. She will also not remember Marina.
Kitty is now movie-verse Kitty from the X-Men movies (pre Days of Future Past). She's very intelligent, has a massive crush on Ice Man (but not really seeing him, yet, because Rogue), and isn't quite as super bubbly as Evo!Kitty. She's also just made the decision to keep her powers despite Rogue considering giving her own up by using the serum. As with my others, she won't remember Marina.