A forum member who wants to pretend he's no longer on this forum has been responding (poorly) to this thread via PMs, and most recently claimed that '70 years' can be seen "both ways", apparently meaning that the 70 years can be counted with or without travelling time.
That is, of course, illogical, because in the JW belief, the 70 years includes the travel from Judea to Babylon (supposedly starting in October 607) and from Babylon to Judea (supposedly ending in October 537).
Apart from indicating that the person does not have a good grasp on logic, this also demonstrates well that the JW interpretation doesn't even allow for "70 years at Babylon". Since the Bible elsewhere suggests that such a trip can take about 4 months, and the 70 years (in the JW interpretation) purportedly includes two such journeys, the period "at Babylon" was about 69 years and 4 months.
Perhaps the new NWT should include some annotations for the verse:
10 “For this is what Jehovah says, ‘When 70 years at Babylon (actually 4 months of travelling to Babylon plus 69.3 years at Babylon plus 4 months of travelling to Judea) are fulfilled, I will turn my attention to you, and I will make good my promise by bringing you back to this place (even though you'll already be back here).’