absolutely no point and yes you would be repeating your earlier studies (think foundation level units 1 to 3 for ICB levels I and II).
The reason that some people take the ICB route when they already have a higher level qualification is for MLR cover and access to cheaper PII cover. However, assuming that you already have your post qualification experience could you not just set up under your AAT banner as an MAAT MIP? MLR cover and cheaper PII (again through Trafalgar) would then be available with the AAT.
Pretty sure that there's now going to be a follow up question as that feels too short to be a proper answer.
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Shaun
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