Thank you for bringing this up and it is a very valid question!
To answer it, as we explained in the initial notification and in followup clarifications on the forums - the new licensing would only affect new licenses purchased after December 6th. This means that existing SE clients would keep their licenses with the exact same setup as they were when they initially purchased them. In other words, when 6.3 comes out for example and existing SE clients download the new license key for it - they will get the new features introduced with the new release, the bug fixes, etc. but their license setup would remain the same, i.e. with A/B testing and without Mobile add-on included. For them the Mobile add-on would still remain an optional add-on as it has always been.
So essentially, as long as you have active subscription for your licenses they will have the respective license keys for all versions available to them. The only thing that would differentiate between new and the old SE package would be the date when they would purchase and that would define whether they get the Mobile add-on included by the default, whether or not they get the A/B testing included and also the price of the SE license.
Let me know if this makes sense and in case you have any other questions on the matter.
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