Wouldn't the B variant show higher session count? If your A/B testing tool doesn't detect imbalances in cohort size I would imagine you have a bigger problem, since it's easy to accidentally measure the A and B groups differently.
> We explicitly only changed the infra which served our landing pages, and kept the content - the HTML/CSS/JS - identical. Once the new infra was shown to work, we would begin to experiment with the website itself.
- http://alexeymk.com/2020/07/14/lies-damn-list-and-front-end-...