The Transfiguration Future Millennium or Restoration of the Kingdom in 70AD?

Is the Transfiguration of Matthew 17 the yet future 1000 year reign of Christ on earth according to Pre-Tribbers? Is the beginning of the Millennium in the 6000th year since Creation or is it the consummation of the age and restoration of the kingdom to Israel in 70AD?

Will Elijah the Prophet appear before an alleged future end time to preach that the kingdom of heaven has drawn near? Why did Jesus lay the axe to the root of the trees and have the winnowing fan in his hand in the first century?