If I remember right, the organiser handbook refers to repeating loops. It does not refer to repeating a stretch of road in the same direction.
Also, bear in mind AUK routes are defined by controls. Not the roads between them (which are at the rider's discretion). Even though the distance is based on the shortest route between controls. Confused yet?!?
So (A,B,C,D are controls and > means "ride to")
A>B>A is ok
A>B>A>B>A is not
A>B>C>A>B>D>A is likely to be ok (provided D is sufficiently different to C)
A>B>C>A>B>C>A is not
A>B>C>A>C>B>A is ok.
etc. Clearly there are lots of variations on this. And bear in mind that it is all subject to the confirmation of AUK (who have delegated checking route validity to the DIY organisers, Perm Secretary and Event Secretaries/Co-ordinators).