One extension goes via Rossmore, Bringelly and North Bringelly to Badgerys Creek Airport.
The other extension branches of the above line between R and B with stations at Maryland and Oran Park to Narellan.
The line at the Narellan terminus is aligned so that it could continue to Macarthur.
Note the possible confusion in the names Maryland and Merrylands.
Note that the Geographical Names Board doesn't like "South", etc, in the names of suburbs.
The map finishes at BC Airport, so it is not known how this line might continue to say St Marys.