As noted, Batista will be returning to WWE on January 20th at RAW and will be around through WrestleMania XXX.
The idea is that this is not a one-time WrestleMania deal, but rather a “last run” for Batista that could go as long as two years. Through his new deal, he’s expected to take at least some time off this summer to promote Marvel’s Guardians of the Galaxy movie.
Regarding his return on the January 20th RAW, he will not be wrestling that night. His first match back won’t be until the Royal Rumble 30-man main event.