Ooh, just found this out about the building I work in

February 17th, 1939
Millers Department Store building (now the Civic Offices) opens. Designed by G. A. J. Hart, the building contained the South Island’s first escalator.

November 12th, 1980
New Civic Offices (formerly Millers Department Store) officially open.

And the escalators are still here ...

Source: Library: Chrisrtchurch Chronology 1939