I agree, it was really misleading.
Customers want to know what options they have, and they want those options to be communicated clearly.
It seems that the pre-sale "bonus" was just access to the download link a day early (which isn't a bonus that would particularly attract me, but clearly appealed to some), but it wasn't clear at the time that the DSF Strings pack would still be available post-release. I don't recall the cut-off date being very clear either, but maybe that was just me.
At the time it seemed that the DSF strings pack was the pre-sale bonus but then it transpired that it was the early adopter bonus, available to download customers until the end of September and to purchasers of physical stock from third parties until the end of October... except the store page I just checked for the X2 Pro upgrade still lists the DSF Strings pack as if it is available for download customers at the moment (so I have no idea whether it still is or not).
It would have been more straightforward if Cakewalk had just issued a statement that any X2 Pro registration before the end of October would qualify for the DSF Strings pack, then people would have had an opportunity to sort out their options and cashflow.
I like the freebie for early adopters (and I like the Content Club idea), but it was not communicated clearly enough.