ArcGIS Online drive-time analysis [walk distance]

[RobertSteele]

Hello,

Im using the walk-time analysis tool in ArcGIS Online.  This is producing walking distance maps (800m) from railway station points.  However, it would appear not to be using a network that includes paths, or pedestrian bridges (see attached example that fails to consider walkers using the pedestrian bridge over the railway).  

Please can anyone confirm the network being used, or suggest how i can view it, modify it or speak to its administrator?  It would appear as though only the road network is being used, not a dedicated path+road network.

Any advice on producing something more reliable in arcgis online?

Thanks, Robert