Hi,
You are correct about the new ANO.
However, as I understand it, you still do not need a microlight rating on an ICAO licence.
But,
by allowing a microlight rating to be added to one, the CAA are acting kindly in that it makes it clear that if you have a UK PPL(A) or a JAR SEP and no longer wish to fly "light aircraft" (for the moment at least) but only want to fly microlights under the "privileges" of those licences, you can now apply for a microlight rating and thus be eligible for the UK microlight medical. (which, of course, won't be recognised by the IAA!!)
Previously, the use of a microlight medical by a PPL(A) holder who only wanted to fly microlights was by "dispensation" and I don't think it was possible with a JAR licence.
That's my take on the situation!
Basically, it is hard to get rid of grandfather rights as well.
The British Microlight Aircraft Association will be able to help out more than the CAA, I suspect, since they sit in on all the negotiations on changes to the ANO as regards microlights.
Very best,
XA