Some variables exposed on this topic. This will be available to all games if the EXE has been generated today or later (obviously if before, this won't be in

spoBaseTimeEntrench = 7 // Base time in days for a level of trench (this is per level of trench to reach)
spoHarshWeatherEntrench = 2 // modifier per level
spoVeryHarshWeatherEntrench = 2 // modifier per level
spoNonClearEntrench = 1 // modifier per level
spoStrategicEntrench =-1 // modifier because of Strat value of leader, not per level, but single, flat discount