I’ve been under the impression that the tribulation was the 7-year period following the rapture. Based on your most recent post it seems a distinction is being made between God’s wrath beginning in Rev 16 and the Great Tribulation starting in Rev 13. Could you amplify?
Rev. 6:15-17 state that God’s wrath will have already begun by the time of the 6th seal judgment which takes place early in Daniel’s 70th Week, just after the rapture. The great tribulation begins in the middle of Daniel’s 70th Week as described in Rev. 13 when Satan is expelled from heaven and comes to Earth to indwell the anti-Christ. This leads to the abomination of Desolation spoken of in Daniel 9:27 and 2 Thes. 2:4. In Matt. 24:15-21 Jesus identified this as the beginning of the Great Tribulation.