So you agree with Heiks that the first four trumpets have sounded already? before 1844? The first and second angels messages were historically given between 1842 and 1844 but I think you're saying they especially apply to the future when the three woes sound, is that right?
As previously stated I believe six trumpets sounded before 1844.
The unfolding of the three angel's messages was given in the seven THUNDERS, not the seven trumpets.
The seven thunders begin sounding when the 1st and 2nd angel's messages first began to be proclaimed around 1840 - 1844
We also see those thunders starting to roar, near the end of the sixth trumpet, in Revelation 10.
After these seven thunders uttered their voices, the instruction comes to John, as to Daniel, in regard to the little book: “Seal up those things which the seven thunders uttered.”. . . John sees the little book unsealed. . . . Then Daniel’s prophecies have their proper place in the first, second, and third angels’ messages to be given to the world.... The special light given to John, which was expressed in the seven thunders, was a delineation of events that would transpire under the first and second angels’ messages. . . . The first and second angels’ messages were to be proclaimed, but no further light was to be revealed before these messages had done their specific work. . . . {CTr 344.4}
Thus the first four trumpets cannot refer to the three angel's message, i those messages are part of the seven thunders, which appear at the end of the sixth trumpet,
