Simply put the distance to destination countdown is well not couting down the distance to destination. Cane Creek Route...
More information might be helpful? Is it staying at a particular distance for the whole length of the route, on a particular service or just any service, with a particular loco or any loco... Hard to recreate "It ain't working guv"
I tried starting from different locations one 30 miles away one 5.6 mile away the starting distances never counted down as i headed toward the destination i wanted to end at.When i got to the end it still said i was 30 mile away and 5.6 miles away after both trips,i suspect maybe some update may have affected the counter since i tried a different route and it's distance count down worked.