In the passage before us we come to the concluding vision of the series of visions that Zechariah received on one night. The next visions are not received until a later date. The last date mentioned in Zechariah 1:7 was where the visions began; it is not changed until Zech. 7:1.
In a sense, Zechariah has come full circle in this series of visions. In his first vision, recorded in Zechariah 1:8-11, he saw the vision of the Four Horsemen on horses colored similarly to the horses pulling the Four Chariots in Chapter 6 (Zech. 6:2-3; 1:8). Those Four Horsemen were also in a valley, as are these Four Chariots (Zech. 6:1; 1:8).