I like the following way of looking at the 3 feasts:-
Passover - the barley harvest - barley needs little agitation to separate husk from seed. Represents the overcomers.
Pentecost - the wheat harvest - wheat needs threshing to liberate the seed from the husk. Represents the rest of the church.
Trumpets - the grape harvest - with their thick skins the grapes need the full bruising of the wine press to liberate the juice. Represents the unrepentant.
All 3 types of ‘produce’ are required for God’s great harvest celebration (the God who makes ALL things new).
They can be seen to correspond to Paul saying 'As in Adam all die so in Christ all will be made alive but each in his own order (or squadron)…
The firstfruits
Those that are Christs at his coming
The end
(not all agree there are 3 squadrons - some say only 2 - but bizarre to have the metaphor of groups of people which are just 1.Jesus 2.all Christians)
Coupled with the Jubilee where all debts are cancelled even if a man has not found a kinsman redeemer seems to clinch it for this sinner.