Am I the only one who did notice that Celeste/Sabine was manipulating a Davina-Voodoo doll all over the episode she died in? Bringing her to earth, water and fire? Sliting her throat (the doll's) in the end to gather Davina's blood to complete her own ritual, hijacking the harvest ritual powers?
Davina wasn't dying due to the harvest not being completed and elements taken over. It was Celeste working dark magic on her! Something her former body was banned for from the circle! It all started and went way too fast too, whenever she was playing with the voodoo doll it got worse. Davina would have been able to sit the harvest out as planned otherwise, but we all know by now that it was Celeste's plan from the start to not let that happen but steal those powers for herself! And Sophie of course didn't get it as usual and brought up the wrong conclusion - just as Celeste had intended to.