Well, for those interested, I left Montville at 0400 and 1600 found me a third of the way down the Putty Rd. Apart from taking a short cut about 20k before Grafton And the Wooten way I stuck with the script. So that's 1050k in 12 hours even with the road works including two lazy 25 mins stops for brekkie and coffee. As far as speed goes, the Children were thought of. They aren't getting my money that easy again!
Conclusion is even with the roadworks the route is viable as long as you aren't on a BBG mission.
However the grinding dullness of the road eventually got to me, so exited stage right to Singleton and the Putty Rd. Sooooo worth it.