Description:An intensive 3-day course focusing on materials and concepts of a technical nature, which will culminate in an examination. The cost of the course is $4,985. For individuals that pass the examination, the Uptime Institute will award an Accredited Tier Designer endorsement.
Eligibility: Intended for licensed Professional Engineers.
I got this one and was quite happy. It is Tier centric, but also usefull to refresh you electrical and cooling knowleges. Also instructors with the real practical experience are open to discuss any questions during breaks.
Sorry, somehow I was missed you question. As far as I know now there are no requirements to retake course . I am going to visit this May Uptime Symposium, so I will get an opportunity to ask them directly.