>>67747686That last tweet was on 31 Dec, at 1.45 am PST. 30 days after that moment will be this coming Tuesday.
The voice pack sale ends on Tuesday at 6.59 am PST - 30 days, 5 hours and 14 minutes after her last tweet. One minute after the sale ends, the clock will strike midnight JST to start 31 Jan.
Dunno if they'll publish the notice at that moment, especially since they have the Niji EN Mario Kart tournament starting just 12 hours later, and the announcement will heavily impact the other livers' morale regardless of when they actually make it. But they might be petty enough to announce it in the window between one hour before it starts and one hour after it ends; possibly during the race, so that the livers either won't notice because they're too busy streaming, or will be forced to pretend to be too busy streaming to notice.
But my guess for the earliest possible announcement time will be 12 hours after the start of the tourney -- 7.00 am PST on 31 Jan (W), and midnight JST on 1 Feb (Th). This way they technically won't lose 2 of their biggest female streamers in the same calendar month, and can avoid embarrassing themselves in front of the shareholders.
Slightly more likely than Thursday at 0.01 am JST would be 20-23 hours later, at 3.00-6.00 am PST.