Something else I want to point out about the Vials of Rev.16.
Many say, especially those on Pre-trib, believe those vials are all about God's Wrath poured out upon the beast, and upon the wicked, and that Christ has already gathered His Church before they start. Even some brethren who are Post-trib believe Christ gathers His Church immediately prior to those Vials being poured out upon the earth.
Ask yourself while reading the following events of the 6th Vial, exactly who is doing the wrath here, and who is it upon in that time?
Rev 16:12-14
12 And the sixth angel poured out his vial upon the great river Euphrates; and the water thereof was dried up, that the way of the kings of the east might be prepared.
13 And I saw three unclean spirits like frogs come out of the mouth of the dragon, and out of the mouth of the beast, and out of the mouth of the false prophet.
14 For they are the spirits of devils, working miracles, which go forth unto the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty.
(KJV)
Do you see there anything about God's Wrath being poured out upon the beast? No, you don't.
It's because it's a time of the beast's wrath upon the earth, not God's Wrath poured upon the beast. So the 6th Vial is not about God's Wrath upon the beast at all.
And what TIMING is the beast's wrath upon the peoples on the earth? That is TRIBULATION timing there.
It is then that our Lord Jesus reminds His Church on earth that He comes "as a thief", and then at the ending of that 6th Vial gathers Satan's host of armies around Jerusalem in order to pour out His cup of wrath on them at the 7th Vial:
Rev 16:15-17
15 Behold, I come as a thief. Blessed is he that watcheth, and keepeth his garments, lest he walk naked, and they see his shame.
16 And He gathered them together into a place called in the Hebrew tongue Armageddon.
17 And the seventh angel poured out his vial into the air; and there came a great voice out of the temple of heaven, from the throne, saying, It is done.
KJV