She lost weight for her role as Rosa in s02 The Tunnel which she shot in the UK between s01 and s02 of Killjoys so she beefed up a bit during filming s02 Killjoys - if you compare her in s02e01 and the s02e10 of Killjoys you'll notice a 10-15 lb muscle difference. It's subtle but it's there.
"Oh behold.. ye who do not respect your enemy", Sun Tzu

Not just you. I thought so too, during the earlier episode, but I think it must have been makeup and lighting because she was looking much healthier recently. In the first season she had great hair, this season she's been bedraggled the whole time. I think that adds to the effect.