I have talked to my friends at Rosenbauer and learned that this rig is a special design for Australian fire serviced. No-one else seems to have any use for a 20 metre aerial!
They do build both 18 and 22 metre aerial ladders, towers and platforms, of course, but these are almost always on compact short wheelbase chassis. Dresden experimented with a regular pumper sized quint with an 18 metre ladder, along the lines of some units specified by a Turkish brigade, but did not pursue the idea...
This is one of several of such units operated by the South Australian Metropolitan Fire Service in Adelaide and stationed at Woodville. There is no Woodville Fire Department.
Added by Rob Johnson on 06 July 2021.