The group claiming a date for this to happen (29 Jul 16) is wrong twice: we are not to set dates for His return, and also, the events of Revelation chapter 6 (and others) do not occur until the Tribulation begins. The Tribulation has not begun, and won't begin until after the Rapture of the Church.
The Rapture is not Christ's second coming either. He returns in the air to retrieve (snatch away) His bride and bring them to heaven, instantaneously. His actual return will come at the end of the Tribulation.
However, having said that, the events of Revelation (and Revelation Chapter 6) will occur someday.
That is sober food for thought, and should give people pause.
6 I watched as the Lamb opened the first of the seven seals. Then I heard one of the four living creatures say in a voice like thunder, “Come!” 2 I looked, and there before me was a white horse! Its rider held a bow, and he was given a crown, and he rode out as a conqueror bent on conquest.
3 When the Lamb opened the second seal, I heard the second living creature say, “Come!” 4 Then another horse came out, a fiery red one. Its rider was given power to take peace from the earth and to make people kill each other. To him was given a large sword.
5 When the Lamb opened the third seal, I heard the third living creature say, “Come!” I looked, and there before me was a black horse! Its rider was holding a pair of scales in his hand. 6 Then I heard what sounded like a voice among the four living creatures, saying, “Two pounds of wheat for a day’s wages, and six pounds of barley for a day’s wages, and do not damage the oil and the wine!”
7 When the Lamb opened the fourth seal, I heard the voice of the fourth living creature say, “Come!” 8 I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a fourth of the earth to kill by sword, famine and plague, and by the wild beasts of the earth.
9 When he opened the fifth seal, I saw under the altar the souls of those who had been slain because of the word of God and the testimony they had maintained. 10 They called out in a loud voice, “How long, Sovereign Lord, holy and true, until you judge the inhabitants of the earth and avenge our blood?” 11 Then each of them was given a white robe, and they were told to wait a little longer, until the full number of their fellow servants, their brothers and sisters, were killed just as they had been.
12 I watched as he opened the sixth seal. There was a great earthquake. The sun turned black like sackcloth made of goat hair, the whole moon turned blood red, 13 and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind. 14 The heavens receded like a scroll being rolled up, and every mountain and island was removed from its place.
15 Then the kings of the earth, the princes, the generals, the rich, the mighty, and everyone else, both slave and free, hid in caves and among the rocks of the mountains. 16 They called to the mountains and the rocks, “Fall on us and hide us from the face of him who sits on the throne and from the wrath of the Lamb! 17 For the great day of their wrath has come, and who can withstand it?”
Revelation 6
The events described are horrible. Death. Famine. War. Worldwide economic collapse. Starvation. Enslavement. And, a worldwide earthquake followed by global devastation.
Could a rapid, magnetic pole shift, where the crust of the earth shifts over the underside mantle, cause a horrible global earthquake? What would cause the "sky to be rolled up like a scroll" other than massive pressure roll clouds as the atmosphere attempts to keep up, causing massive winds and horrific damage?
The folks who set a date and put that website together may be partially misguided, but they also point to a possible explanation for a certain horrifying event described in Revelation.
My prayer is that I am not around when this happens. My prayer is to be taken by Christ before the Tribulation begins.
"Be always on the watch, and pray that you may be able to escape all that is about to happen, and that you may be able to stand before the Son of Man."
Luke 21:36