It depends a lot on incubation temperatures. A cooler incubated clutch can take far longer - but you have to be carefull not to go to too high a temperature as well as you will face deformities, fatalities and other complications.
You have to make judgements - I typically incubate at 86-90f and expect pipping at around 58-60 days. Monitoring them through candling works best and don't cut until you absolutely know they are ready - best guide for this is when the first one pips the egg on its own to be honest. Even then you have to take care of the eggs you cut open.