The great Northern exodus appears to have started, we are travelling to Brissy on the Bruce highway, todays leg is Proserpine to Bororen stopped for lunch at the Rocky leagues club.

So between Prossy and Rocky we saw more than 100+ vans heading north, of them I would say less than 5% didn't have towing mirrors, extendables seems to be the majority with other type being a close behind.

However there were a few that were towing hybrids or narrow van without any additional mirrors.

The second part of the journey Rocky to Bororen, we saw a couple of dozen caravans heading north all of them had the correct mirrors.

Urban Myth or Furphy busted by my non scientific observations.

*postscript* It appears that the majority of vans observed were setup correctly, but the worry would be the full size single axle vans some looked very dodgey, either too low or too high at the rear,