Uncle, the words “after these things I will return” are from Amos, not James. James quotes them as fulfilled in the first century. Note in v17 that Amos said the tabernacle of David would be rebuilt “that the residue of men may seek after the Lord, and all the Gentiles...”
The problem dealt with in the Ac 15 meeting was the Jewish/Gentile problem. If you’re a Gentile, Uncle, and Amos isn’t fulfilled, you cannot seek after the Lord.
James quotes them as fulfilled in the first century.
Without an unstated gap on n centuries between one word and the next.
Apropos the subject of temples, I'm finally reading G. K. Beale's book The Temple and the Church's Mission. Very interesting. Beale gives many, many examples from the Bible and contemporary Jewish sources to support the assertion that the Jews of the time did not regard the stone building as final.
The author gives an 1.5 hour summary here.
Nope. Amos's words are "In that day ..." [Amos 9:11]. James's are different.
James quotes them as fulfilled in the first century.
Nope -- He's prophesying about when Jesus will return for those present -- which will be "after this", in other words, "after God visits the Gentiles to take out of them a people for his name".
Note in v17 that Amos said the tabernacle of David would be rebuilt “that the residue of men may seek after the Lord, and all the Gentiles...”
Note in the passage that "all the Gentiles who are called by My name" has already taken place before "the tabernacle of David would be rebuilt". So then are you saying that Gospel went out to the Gentiles before the death and resurrection of Jesus???? Your understanding has the cart before the horse.