WWE Payback is not yet sold out but is expected to be a sell out by this weekend, which would be considered impressive due to how high ticket prices were.
The old Raw and Smackdown rosters are actually scheduled to remain effect for this weekend and 4/23 is supposed to be the last day before all the lineups are changed.
What this means is that the Smackdown-to-Raw taent like Miz, Dean Ambrose and Bray Wyatt are doing three shows per week (Saturday, Sunday, Monday) while the Raw-to-Smackdown talent like Kevin Owens, Sami Zayn and Charlotte are having to do five (Friday, Saturday, Sunday, Monday, Tuesday).
Source: Wrestling Observer Newsletter. Subscription information & prices available at f4wonline.com