The change or pre-req from CS 641 Foundations in Data Science to CS 601 Programing Methods for Data Science or BS in CS or Equivalent recognizes that the real content needed for 651 is strong programming skills, rather than the knowledge in 641. The new pre-req parallels the pre-req for the undergraduate version CS 351 which has CS 102 as its pre-req.
Farmer, Michael, "2/17/2021: Course Change Form CS 651" (2021). UCC Documents. 16.