Creature with the Atom Brain Daybill is a great looking Sci Fi / Horror Australian movie poster but the Robert Burton printers details are a strong clue that the poster was issued some years after the original US release.
Creature with the Atom Brain was actually banned by the Australian censors in 1955 due to its horror content and only released in Australia somtime between 1969 and 1971. Australian lobby cards were produced for Creature with the Atom Brain probably because the original US lobby cards would no longer have been available.
It is interesting that Creature With The Atom Brain was passed by the censors in New Zealand in 1957 with a R13 rating and completely uncut. However, it is likely that US posters might have been used for the New Zealand release rather than daybills. It was quite common for New Zealand to use posters from other countries to promote their films.
Although Creature With The Atom Brain was released in Australia many years later than the original US release, the value of the Australian daybill does not seem to be affected. In fact the artwork is significantly better than many other Robert Burton daybills that were printed in the 1960s.