I don't think Cam has gone from prudish to going to the hideaway with Jamie overnight. In the beginning I saw someone sweet who coupled up with Jonny out of chance, I don't think she liked him that much but being together 24/7 with people warps feelings. I thought she was becoming more confident and out of her shell as the weeks went on and then the Jonny and Tyla situation happened. So she retreated back into her shell for a couple of days and then the new boys arrived. I think this is when she gained her confidence back and it's been going up since then. We have to remember editing is huge and they will create the characters they want. They are clearly going for a Sandy from Grease theme for Cam.
I think Gabby and Marcel are going through the editing problem right now. They were too clear cut as winners so production had to spice it up. A few islanders who have left the villa have defended Gabby and Marcel saying what we see isn't necessarily reality (in reference to Gabby being cold towards him).
Chris for me is the person who had the personality transplant. We got a glimpse of 'old Chris' at Casa Amor and we keep hearing islanders agree he says mean things to Liv as well. I don't buy his quick turnaround.