The 6 months wait is a definite, its down as an endorsement on my permit (which tallies with a telephone enquiry I'd made to Ballina), and the description of the categories to which it applies specifically says EB.
The compulsory lessons I was told at the tax office, so maybe they're not fully correct. As its an "off-beat" issue its hard to get good info on it.
I just notice that there's a further endorsement on my learner permit - that I must be accompanied by a fully qualified driver (EB presumably, since I've already a full B myself)- what a joke, given the number of full EB holders its just unrealistic.
So, given the way they apply the rules, unless I saw it written on an official document that EDT (12hrs training) does not apply to EB, then I think the wiser course of action is to get the permit before 4 April.