Regarding Elijah, one thing to keep in mind is the multiple meanings of the term “heaven” in the book of Kings. One is God’s kingdom, one is the physical universe/outer space, and one is the earth’s physical atmosphere/the sky above. God moved him out of harms way to a safe place, so being taken up in a “whirlwind to heaven” doesn’t mean God’s kingdom where Christ resides. Remember, Elijah later wrote a letter to King Jehoram after he was “taken up”, see II Chron 21:12.
“...the LORD would take up Elijah into heaven by whirlwind,....” 2 Kings 2:1
Well, even if you place Elijah in the lowest form of heaven, he’s defying gravity.
But take look two verses earlier, at 2Kings 1:17....
“So he died according to the word of the LORD which Elijah had spoken. And Jehoram reigned in his stead in the second year of Jehoram the son of Jehoshaphat king of Judah; because he had no son.”
The writing that you speak of was not very many years after Elijah departure. The Jehoram that received the letter was a king of Judah, and just a few years earlier, became king while his father, king Jehoshaphat was still king of the same tribe (so say some researchers that compared all the chronological data of the OT kings). So, Elijah already knew how evil Jehoram of Judah was, even before his being taken up from this earth.
That said, keep in mind that Elijah was a prophet, and was given words of prophecy, such as his instructions from God to anoint Hazael to be king of Syria, and Jehu to be king of Israel, and Elisha “to be prophet in thy room”. (1Kings 19:15,16).
Well, Elijah personally anointed Elisha, but Elijah didn’t personally anoint Hazael or Jehu; Elisha did, after his mentor’s departure (in Elijah’s stead, or “room”).
Same with any writing of prophecy from Elijah. Elisha was his right hand man, possibly his record keeper. He held that assistant status for several years, it would seem. It may have been the last prophecy given by God to Elijah.
So, I tend to think that when Elijah went up out sight, he was loooonnngg gone.