I guess I'm a pretty slow to catching on to things because I have just noticed some discussion about this paragraph in the WT's 'Isaiah' book.
***ip-1chap.19p.253JehovahProfanesthePrideofTyre***
"SheMustReturntoHerHire"
21
Isaiah goes on to prophesy: "It must occur in that day that Tyre must be forgotten seventy years, the same as the days of one king." (Isaiah23:15a) Following the destruction of the mainland city by the Babylonians, the island-city of Tyre will "be forgotten." True to the prophecy, for the duration of "one king"—the Babylonian Empire—the island-city of Tyre will not be an important financial power. Jehovah, through Jeremiah, includes Tyre among the nations that will be singled out to drink the wine of His rage. He says: "These nations will have to serve the king of Babylon seventy years." (Jeremiah 25:8-17, 22, 27) True, the island-city of Tyre is not subject to Babylon for a full 70 years, since the Babylonian Empire falls in 539 B.C.E. Evidently, the 70 years represents the period of Babylonia’s greatest domination—when the Babylonian royal dynasty boasts of having lifted its throne even above "the stars of God." (Isaiah 14:13) Different nations come under that domination at different times. But at the end of 70 years, that domination will crumble. What will then happen to Tyre?
In this one paragraph they admit that Jeremiah 25 is talking about babylonian supremacy, that the 70 years doesn't have to be exact, and that 539 is the date when it ends. How in the heck can this be held while at the same time they keep the idea of 537 and the exile?