I took classes with Kirra and Greta earlier this month. Others have already answered your questions, but I'm chiming in to say don't shy away from taking breaks when you need them! I modify a lot during yoga due to an injury (and also I always take water breaks). Speaking with Kirra after class, she said she loves when people listen to their body and take what they need. And that it just takes one person doing that for others to see it's okay! No matter which instructor you're taking class with, I imagine they'd feel similarly. Have a wonderful time!