Me too, I thought her departure would be a temporary storyline but they removed Sandrine Holt's name from the opening credits so it looks like she's left the show permanently. Meredith Eaton is still being billed as a guest star so not sure if she's permanent or not, pretty confusing.

Sandrine Holt was the reason I started watching this show in the first place. But I grew to enjoy the whole show. But I still miss Sandrine.

I see that they added Meredith Eaton to the main cast in yesterday's episode so I guess she's a permanent member of the team now, looks like the Thornton double agent story is finished now.