The system calculates the inflation time based on tire volume, 4 vs 6. I think the 6x6 wrecker setting for Highway is 82psi which could have the cold temp issue. If the system is cycling due to cold you can vent the wheel valve cover screw and re-tighten, this will reset the valve to the ambient temperature. This would not help at high temperatures as the pressure in the cover would be helping the valve to close at higher tire pressures.What faults do you suspect would appear??
Overinflate? Based on what? As in not the 50ish-lb the previous trucks were set for??? But then again.... maybe those were under inflated thus decision to change to the 6x6 settings? How much you suspect the pressure will drop in temps below 50 and wouldn't the ctis adjust as the tires got warm while driving?