Also a number of insulators mounted to the top of 2 portal structures for 25kv isolation switching. No doubt so power to the points yard/platforms/area under the bridge can be made safe when needed.
Also a few cantilever arms up in Platform 2, I didn't see if any others installed. Portable lifting platforms stored between tracks so they can finish the job. So much for claims of needing a huge shutdown to install all the wires.
They may be able to get much of the catenary wiring done without a shutdown, but what about the upgrade to the signalling to make it compatible with the 25kV traction supply?
So far, the lines south from around Mile End (I think) have been resignalled with axle counters etc., but the Adelaide Station Yard still has the old track circuit system installed. Presumably these signals are no more compatible with high voltage AC than anywhere else on the network.
Given the complexity (they would need to do all the Port & Gawler side too) and recent experience with signalling it's unlikely they could re-signal the whole yard without some period of closure.
Also, around the station throat (Morphett St bridge) and out to Nairne Junction, there are still points, crossings and track into platforms 1 - 5 which have not been renewed. Some of the track is still on steel sleepers and looks distinctly "old school TransAdelaide".
Fair enough, any trains, diesel or electric, will be moving pretty slowly through this area, but it would be a shame if the only part of the Adelaide network which does not get a full track rebuild is Adelaide Station itself (and the Grange branch).
My opinion is they could possibly manage the wiring with overnight & weekend work, but some sort of shutdown is still on the cards for the signalling upgrade, and maybe the last bit of track renewal.