The project was originally scheduled to run through to October but the good conditions and progress of council and contracting crews had reduced that.
Work had now begun on the sixth stage of the programme of Tennyson and Emerson through to Shakespeare Rd and involves laying new stormwater drains as well as a new design layout.
The upgrade follows the upgrade of the Hastings St underground infrastructure, and the street surface between Albion Lane and Emerson St last year.
The above-ground design, which will be carried through the full CBD stretch of Hastings St, includes wider footpaths, a revamped parking layout, new plantings and street furniture to give it a more comfortable pedestrian and shopper feel.
Mr Kingsford said the council would make the general public and retailers in the area aware of any potential traffic flow disruptions in the areas.
Planning for this stage of the CBD upgrade began in 2010 and is part of a city-wide response to flood-prone areas.
All the major new pipelines will connect through to the Marine Parade stormwater outfall underneath the viewing platform.