Well.... I believe that there will be plenty of those who will not be ready when the Lord comes to gather his church, who will have read the word of God and will know his word and will realize what has happened after those who were ready have been removed. At that time I believe that they will get their selves together and realize what time period they are in and what they are going to have to go through. I believe that this group will begin to alert people in the beginning of that seven years in regards to what is going, who the ruler is that makes the seven year covenant and the seals, trumpets and bowls that, for them, will be about to take place. But, I also believe that the 144,000 will be spreading the gospel as well, but as mortal men out of Israel and not as those sent from heaven
The redeemed would be speaking about living people, redeemed from the earth is what the scripture says. Also, there is no scripture that specifies that it was the 144,000 that Jesus was preaching to in Sheol. That claim would by conjecture only.
Scripture states that the woman/Israel, will give birth to the male child, which means that 144,000, twelve thousand from each of the tribes mentioned, will come out from Israel as the first fruits to God, acknowledging Jesus as their Messiah. In the middle of the seven years, they will be caught up to God's throne, just like the living church at the time of the resurrection.
The above would only be true if one believes that the 144,000 come from heaven. I believe that this 144,000 will be a select group of mortal men, reserved by God as the first fruits out of Israel. These will be the only ones who will be exempt from the 5th trumpet, which are those demonic beings who will be commanded to torment the people of the earth with the stings of their tails.
To be honest, I have never read any scripture that would infer that the 144,000 are sent from heaven. And to relate them as being those whom Jesus preached to in Sheol would only be conjecture. There is much controversy regarding who those prisoners were that Jesus went to preach to. I personally would lean more to the idea that Jesus preached (made a proclamation) to those angels who are mentioned in Jude 1:6 and 2 Pet.2:2-4, as those who took wives from the progeny of men (Gen.6:1) for the purpose of contaminating His blood line and thereby attempting to keep scripture from being fulfilled. Jesus went there to proclaim his victory to those angels who were imprisoned.