Shopify Plus members using checkout scripts for their integration may notice a discrepancy in the cart prices during preview mode that will go away once a test is live if they are testing prices that are higher than their control price! The control price and any price groups lower than the control should show up correctly in the cart if your checkout script is live, while the higher price group will continue to add to cart at the control price.
This is because there is one integration step left, which will occur when the test is started. At that time, the Intelligems app will update the Shopify price to be the highest price in the test, and then for users who are in a lower price group, we will calculate a discount behind the scenes.
If you are only testing prices lower than the control, then you should not see any discrepancies when testing in Preview Mode since the control price is the highest price in the test.