Hi Mario! We will be publishing more details on this on March 7 when we go live, per the blog post - https://techcommunity.microsoft.com/t5/microsoft-syntex/microsoft-syntex-pay-as-you-go-will-be-generally-available-on/ba-p/3749868 - however, we should note that any customer with a per user license of Syntex does not have to "migrate" to pay-as-you-go, they can continue to use all of the features conveyed in the per user license until the end of their Microsoft agreement, including "true up" and "true down" as needed.