All the GUE prerequisites are, in theory anyhow, waverable. In theory you meet and dive with an Instructor Evaluator and show him you have all the knowledge required and can perform all the required skills to standard. Having taken a class with an IE I can say they seem to be pretty hard to impress. That said, I don't know if wavers are a real possibility even though it is in the standards document.
From GUE standards.....
3. Diving prerequisites established by the relevant course standards must be met before trainees can register for that class. Dives cannot be credited across curricula or across levels of a given curriculum. Students may not take two courses at the same time.
Waivers.....
GUE Instructor Evaluators have the power to waive training obligations and award GUE certification based on previous training and experience.
But as you say, very unlikely due to the limited number of IE's out there.
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