text: Are you looking at the tunnel construction running under Parramatta Road? https://www.openstreetmap.org/way/480380426#map=17/-33.87826/151.12941&layers=N
  
  There is no direct connection between the two sides of Alt Street and the intersecting tunnel is (correctly) not joined to the surface level ways.
  
  This is what I see on Cycle Map - are you seeing something different? - https://imgur.com/a/joCr5Wi  