Here is the FAQ:
http://us.battle.net/wow/en/forum/topic/14996569538


A: Once the new regional hardware comes online, players who are already on an Oceanic realm will not be required to take any action to move to an Australian server. Players who are currently on a North American realm will be offered a two-week window to transfer their characters to one of the existing Oceanic realms. While players will be required to purchase a paid Character Transfer service for each character they wish to relocate, full refunds for each toon moved will be automatically processed and returned within 72 hours. Free transfers will begin from 6:01PM AEDT Oct 29, 2014 and end at 6:59PM AEDT Nov 13, 2014. Players will still be able to transfer characters to Oceanic realms after this time, but associated server transfer costs will not be reimbursed.