This article briefly differentiates the Ultimate 12 Standard and Ultimate 12 Plus bundles.
The only and main difference between these two is that Ultimate 12 Standard includes all of the plug-ins in Ultimate 12, except for the Neve-branded plug-ins.
On the other hand, Ultimate 12 Plus includes all of the plug-ins in Ultimate 12, including the Neve-branded plug-ins.
I already own Ultimate 12. Should I purchase Ultimate 12 Standard or Plus?
Both the Ultimate 12 and Ultimate Plus bundles are identical, so there is no benefit to users who have purchased Ultimate 12 in the past.
Ultimate Standard includes all of the contents of Ultimate 12, except for the Neve plug-ins. So, if you purchased the Ultimate 12 bundle prior to this promotion, there is no need to purchase either bundle!