start earliest in morning say 5.30 am, HUB is last point for CNG then you may get it in UTHAL. Maintain average speed of 60 kph (80 kph) and reach khuzdar by noon. A Passanger bus takes 5 hours between KHI & KHUZDAR so calculate avg time for a private car in that context.
Security is not an issue if you are travelling private & maintain low humble profile.
Take break eat well & fresh bbq food only freshen up fill up fuel tank and shoot if you leave khuzdar by 2 at sunset (5.25PM in dec) you can be in Quetta limits. keep dry ration like cream cookies and drinking water bottle with you. ensure that your car is without any problem,
flush coolant to anti freeze when leaving KHI in Dec Quetta will be freezing dead dry in DEC. -- One PW member PKTUN is stationed in Khuzdar do consult him for current security situation.
BTW Quetta is dry in winters skin get cracks like dry desert, paucity of gas will lead to no warm water in lines and electric load shedding put city to rest after 4.00 PM ( after ASR ki namaz)