I don't believe my change goes against the guidelines, as the first link you provided specifically states that motorways should have "limited access via interchanges". This is not true, as while there are interchanges at Nabiac and Bulahdelah, there are three at-grade intersections with major roads (The Lakes Way south, Willina Road, and Failford Road).

Furthermore, the guidelines also state that motorways should be M-roads. This section of the highway is signed A1, so it does not qualify. The Hume Highway is built to the same standard, but since it is signed M31, it counts as a motorway.