True the Bible does not contradict so one's interpretation must be in harmony with not just the context, the Bible book itself and the whole Bible. The 70 years ends with the 'calling to account of Babylon' which according to Jer. 21:12 what is clearly stated in that verse was only after the 70 years was fulfilled and not before that time.
Yeah, "These nations" (Judah and all the nations "round about") serve Babylon for 70 years. The 70 years end, and Babylon is "called to account".
When were the 70 years fulfilled?
From v12, sometime before Babylon was "called to account".
This could only be at the Return of the Jews in 537 BCE and not at the Fall of Babylon in 539 BCE.
That is the most unnatural reading, basically a non-sequitor. It doesn't follow. The 70 years of servitude could not continue past the fall of the government that they applied to. Illogical. For you to say "this could only be at the return of the Jews" is nonsense.
The servitude to Babylon of a specific period of 70 years applied to Judah which also included other nations as stated in Jer. 25:11
Yes, and it was ongoing at the time 25:11 was written, as referenced by v18. It was 70 years of servitude, which had gotten its start before the destruction as a vassal state.
Are you an expert in Hebrew and Bible translation?
Logical fallacy - appeal to authority. But irrelevant anyway.
I concede no such thing. Babylon's calling to account or judgement was not immediate but a process in time as verse 12 clearly explains culminating with its desolation of the land which did not happen in 539 BCE. A careful and not sloppy reading of that verse proves that the judgement against Babylon could only have begun after the Return of the Jews in 537 BCE.
No, scholar. The promise of desolation is in no way connected to the 70 years, either in verse 10 or verse 12. Verse 12 states that the seventy years would end, Babylon would be called to account, and the land would be made desolate. The desolation is not connected to the end of the 70 years, just as the desolation of Judah is not connected to the beginning in v10.
For you to hypothesize that the "calling Bablyon to account" is suddenly a drawn out process that goes beyond the reign of Babylon the most indirect, illogical, ungrammatical reading.