Great job on Brookline, Kevin!
The nodes on Citystrides are brought in from OpenStreetMaps. These maps are open source and can be edited by anyone.
Review wiki for more info on that.
That “OSM” data is updated periodically in CityStrides, If you are close and would like to show that you have completed all the available nodes, it is not inappropriate to mark a street as manually completed while waiting for the OSM data to be re-imported to CS.