Pacific Highway upgrades had given extra numbering inconsistencies in Google Maps. I hv said this before but if u now go beyond the B56 Port Macquarie Interchange where A1 becomes M1 irl, Google maps doesn't recognise this part and is seen as A1
Parts of Princes Highway still have NR1 in some settlements like Berry along with the M1/A1 mess there as Princes Hwy. IRL, it doesn't seem TfNSW will upgrade this route to be full M1 Princes Mwy (or Hwy if we use M31's example)
Its also interesting to note that when in traffic mode in Google Maps, the M31 Hume is the longest dual-highway in Australia despite that there are more M roads that may reach similar lengths (M1 Pacific when its projects are done). For some reason, unless you zoom in really close, M23 Federal doesn't get the green treatment either despite being the same road standard as M31.