SimplyNUC has listed the NUC12DCMi7 Full and the NUC12DCMi9 Full, versions of NUC 12 Extreme with RAM and storage. Both machines are highly configurable and come with powerful Alder Lake processors. The NUC 12 Extreme will start shipping in April at the earliest.
https://www.notebookcheck.net/Intel-NUC-12-Extreme-pre-orders-start-from-US-1-699-with-RAM-and-storage.604549.0.html