What we know so far:
Home: Western Bulldogs, Collingwood, Essendon, Carlton, North Melbourne, West Coast, ?, ?, ?, ?, ?
Away: Carlton, Melbourne, Fremantle, Essendon, Collingwood, ?, ?, ?, ?, ?, ?.
Play twice (5): Carlton, Collingwood, Essendon, ?, ?
Play once (12): West Coast, ? .... ?.
Guessing who else we play twice from the respective groups ...
Group 1-6 (min 1 max 2 ) ?
Our group 7-12 (min 2 max 3 ) Collingwood, Essendon, ?
Group 13-18 (min 1 max 2 ) Carlton, ?
So I would guess the other two we play twice are North from the top group and one of the Dogs or Dees as we play them early on in the season.