"Isaiah’s writings apply to two different time frames simultaneously: (1) Isaiah’s day; and (2) “the last days” or “end-time” (‘aharit hayyamim). When I asked how he knew this he said he had no proof but that it was Jewish tradition. Years later, during my Ph.D. program, I discovered the proof in the holistic literary structures of the Book of Isaiah. These entirely change the rules for interpreting the book. Linear structures map out cycles of events covering many centuries of time, starting in Isaiah’s day...
Isaiah, therefore, uses Assyria’s destruction of the ancient world as an allegory of an end-time destruction. What happened in the past will happen again, only this time it will be with a new “Assyria” and a new “Egypt."
It would thus be a mistake to assume his writings refer mostly to Jews."
Isaiah being sawn in half inside a tree Valenciennes, Bibl. mun., ms. 0007, f. 055. Bible (second quarter of the 16th century)
Isaiah 6:11-13 - Then said I, Lord, how long? And he answered, Until the cities be wasted without inhabitant, and the houses without man, and the land be utterly desolate,
12 And the Lord have removed men far away, and there be a great forsaking in the midst of the land.
13 But yet in it shall be a tenth, and it shall return, and shall be eaten: as a teil tree, and as an oak, whose substance is in them, when they cast their leaves: so the holy seed shall be the substance thereof.
Margaret Barker: The Lead Books Found in Jordan, ~38 min... "Isaiah" + "Zion or calling"