According to The Hollywood Reporter:
"Assuming – as is virtually certain – that the boards approve the proposal, the package would then be sent to the two unions’ membership for a vote, a phase that SAG president Ken Howard and AFTRA president Roberta Reardon are likely to kick off with an announcement at the nationally televised SAG Awards on Jan. 30.
The ballots will probably go out in February, with a return date in March. Within each union, it takes a 60 percent affirmative vote, of those voting, in order to pass a merger referendum. The last merger attempts, in 1998 and 2003, foundered. In both cases, AFTRA passed the resolution, but SAG didn’t. SAG’s 2003 vote was 57.78 percent in favor, or about 2 percent shy of the requisite number.
In the last several years, however, SAG Hollywood members have voted overwhelmingly in favor of pro-merger candidates, which may foreshadow a thumbs up this time around."