New Testament Chronology has some practical use for the data we’ve been considering. It just isn’t as nice and tight as we might wish it was. Still, a general range is far better than vague, wanton ignorance. So let's proceed.
Here's an exercise. Start with *any guess* for Jesus’ birth date. Subtract a 40 week gestation. Subtract another 150 to 180 days (from some point during Elizabeth’s sixth month) and we find the conception of John to be between 61 and 66 weeks before the birth of Jesus. On other considerations, John’s conception should be placed somewhere between two and 26 weeks following the week of Zechariah’s service. That gives a range of 63 to 90 weeks between Gabriel’s appearance to Zeke and the birth of Jesus, whenever that was.
Now, invert that exercise. Working those numbers the other way, if the earliest visitation for Gabriel is indeed late September of 9 BC, then Elizabeth conceived anywhere between October and March. That also puts Jesus’ birth somewhere between December of 8 BC and June of 7 BC, which intersects very well with other evidence suggesting the nativity belongs in that period. (Such as: the Roman census under Saturninus, Joseph’s fear of Archelaus, and the triple conjunction of Jupiter with Saturn.)
This is the practical benefit of considering Zeke, Liz & Gabe, as far as it affects New Testament Chronology. Given these parameters, we can at least test the consistency of an overall view. Of course, the practical details here can also help us reconstruct the story of Zeke, Liz & Gabe, themselves.
To be concluded…