In another scheme to resurface the main route for vehicles in the square, sub-contractors are having to relay the road surface after problems were identified.
SKA's proponents are talking of scattering its sub-telescopes over an area of 1m square kilometres, which would create an effective diameter of about 1, 000km.
The revised plan also includes a new Euston Tube station ticket hall and a sub-surface pedestrian link between Euston and the nearby Euston Square Underground station.