At this point the white road NW to the buildings is not part of Ruscombe Lane, but is LEIGH GATE LANE.  The route of the brown dot dash line heading NE right up to Ridgeback Lane is all part of Ruscombe Lane, as is the white road S into W Milton.  This is confirmed on FMS https://www.findmystreet.co.uk/map search for USRN 43201293 but also on all other maps.  NB Devon Explorer calls it Runscombe but this is a typo, you can select historical maps to see the correct spelling from the 1800s https://gi.dorsetcouncil.gov.uk/dorsetexplorer#map=17.18/50.77160/-2.70306/0&layers=175/100/100//,85/100/100//,2/100/100//,15/100/100//&basemap=1/100/100