The administrator DAN comes up with some discounts on certain products like GAP insurance, but not seen anything on breakdown services, you could contact him (contact details bottom of forum).
Note: Some banks like Lloyds, TSB and others (if you are a customer) do discounts for the AA, check with your bank if they do this.
Also check out for any on-line deals regarding AA, RAC and Green Flag.
I used to be with the AA for decades, but they got far too dear for me, and now with Green Flag who were doing a deal last year.