I used to be of the opinion that the last three ‘unfulfilled’ appointed times of YHVH needed to be fulfilled just as the previous four: right on time, according to the set dates given in Lev 23. BUT, I have modified that, since Jesus says very plainly that NO ONE (except the Father) knows the DAY or HOUR of what we would refer to as the First Resurrection and Rapture (depending on whether one is dead or alive in Christ at that specific set time, which no one can know or alter).
For believers, the trumpet call has been going on now since that Pentecost and taking of the Great Commission to all people — firstly to the Jews — to repent and to “come home”. The death of Yeshua on the cross was not only a Passover event, but an atonement for sin, which fulfills for the believer in Him the Day of Atonements. We also have God’s presence in our midst, which is a pledge of the fulfilling of the Feast of Booths during the Millennial Kingdom. So, while Israel and the nations are still being evangelized until the Day of the LORD comes, we in Christ already have eternal life now, but waiting for the actual reality in due course, both of the resurrection, and of the New Heavens and New Earth after the Millennium.
Should we be misled to think that the rapture must occur on a ‘first day of the seventh month’ — otherwise called a New Moon and also the Memorial of Blowing of Trumpets, then that means we are looking for a specific day, which the Lord says we can not know. If we could know, then so could Satan and anybody else. That would put us in a situation of saying: “He didn’t come this year, so we have at least till next year at this time to wait.” Just as Messiah’s birth was at a time not expected, so will be His second coming, as He has told us. Therefore the advice and warning to be always watchful and in prayer, so that we will be ready, with the Holy Spirit’s help, when that Day comes.
I personally do still think that the ‘last trump’ is connected with the seventh trumpet. There is also the Jubilee trumpet, which is blown not on the ‘Feast of Trumpets’, but on the Day of Atonements. Who is to say whether the Lord, in His wisdom, has not timed the trumpets to suit His own time schedule, which the Father has kept to Himself in this ultimate warfare strategy? The Holy Spirit, who inspired all the Scriptures, surely knew what to inspire Paul to write (even if Paul did not know in advance what John was given to write about the judgments which the seven trumpets herald). In any case, the last trumpet, the Seventh Trumpet is what calls out the Bowls, which are the wrath of God (for a comparatively shorter time, relative to the Tribulation and Great Tribulation), from which we believers are saved by the grace and mercy of our God and Savior.
Thanking and praising God for the blood of Jesus!