Revelation 12:1 is the closing of the time of the Church, next the rapture then the tribulation.

https://video.wixstatic.com/video/33b6b3_f343ef092c8c45d0bb6940d1ca5ac3e5/1080p/mp4/file.mp4

As the time of the Church comes to an end, will we know it? I believe yes and this is further explain using scripture. This means we'll know the approximant time of the Rapture. The saying of Peace and Safety along with a Sudden Destruction as see in 1 Thessalonians 5:3 is Paul giving us the time of when.