That's great news.........now you cab be grumpy and have a good reason :) LOL
For me it was when turning my head to the left and looking up. Sounds like you got a great fit. Of course, if your a lucky guy whose disposition is to smile all the time then you may need to do a refit. You will know. And if you are getting both shells redone anyway, then I say get them redone.
I probably won't do a refit. I don't think there is a perfect fitness that can keep sealed for every position.
I will contact with UM Lab directly to find out why my artworks look like that.