A 8.1-2 vision of summer fruit - ready to be eaten
B1 8.3-8 in that day - songs will be wailing
B2 8.9-10 in that day - songs into weeping
C 8.11-12 the days are coming - famine of the word
B' 8.13-14 in that day - they will fall
A' 9.1-10 vision of the Lord by the altar - everything will be shaken
bookends are the visions,
inside are 'in that day'
and centremost is 'the days are coming'
I think this fits quite well with the whole picture of Amos - having so thoroughly rejected the word of God, God is now handing them over to their sinful desires. Having desired to be free of God's word, he is now deliberately withholding it, with all that goes along with that. This is indeed a dire judgement.