Give O'connells a yell on 0428 591 377 and make sure things are running.
Melbourne - Bright _ Hotham
So you need the 7:10 train. Book here in advance from Southern Crosss to Bright. http://www.vline.com.au/home/
It will take you to Wangaratta on the train. Then you swap to the bus at Wangaratta station and that will get your to Bright at 11:15am. It will cost you about $30. From there you can make the bus up the hill at 1:15 http://www.omeobus.com.au/
If you miss the first train, you will not get up the hill that day. But if you leave Melbourne on the 31st, there are no connections on that day that will get you up there. So you may have to overnight at Bright.
Melbourne - Bairnsdale - Hotham
Going the other way the Bairnsdale Omeo bus departs at 8am, the first train gets there from Melbourne at 11am, and the omeo Hotham bus leaves at 8:30am. So it would take you 3 days to go one side, 1 day (hopefully) on the other.
Osteraria wa, Nihonde wa, arimasen!!