The 'delta' exams allow people who held the older "Base Programmer" and "Advanced Programmer" (the A00-211 and the A00-212 exams) to earn the newest "Base Programming Specialist" and "Advanced Programming Professional" with a shorter, cheaper exam (The A00-233 and A00-234 respectively) rather than taking the full exam (A00-231 and A00-232 respectively).    The delta exams will be retired Dec 31, 2021, but until then eligible candidates can take the delta exam _ONE_ time for free. More details: https://www.sas.com/en_us/certification/resources/delta-exam.html   ... View more