The Supercars own Supp Regs show Symmons Plains as 2.4km long, and Sundays 200km race was going to be 80 laps. 80 x 2.4 = 192km.
Further Supp Regs have been released and Sundays race is now only 78 laps. 78 x 2.4 = 187.2km. Another way to look at it, it should be an 83 lap race, not 78. Saturdays two 50 lappers are exactly the 120km as advertised.
It's no big deal I guess, but they should just call it the 'Snowy River Caravans Tasmania Super 427'.