请教8老师 F4移民Deadline

十几年前我给妹妹一家办了移民申请。Priority date is April 15, 2007. 当几年前她的Priority date 在Chart B到期时，她并不很想继续办理，所以一直拖着。

现在她们一家终于决定办理移民。In July 2023's Visa Bulletin, the date in Chart A （Final Action) became April 22, 2007. In other words, her priority date is now earlier than the date in Chart A (final action).  

我的问题是：

1. 现在才开始办（next step is "step 3 Pay Fees"), 还来得及吗？ 是不是必须在一年内 （i.e., by July 2024) 她必须得到签证Approval (或 完成 Step 11 applicant interview)?  

2. Are there any deadlines for her based on her priority date?

谢谢！