It has indeed, but there is still the not insignificant issues of ventilation shafts (I kid you not - they want to block the formation with vent shafts), and then the arrangement at OOC, where the platform layout means the junction will be severed. Shocking I know, but hopefully able to be mitigated as the WCML branch is planned to be grade separated, and it's far cheaper to do this during construction. The plan as far as I've seen is to reuse a small length of the NNML before diving off into tunnel. Hopefully this means that whilst it'd still be a flat junction, the NNML route could still operate.