Zechariah 1:13-14,16-17 KJV
 And the Lord answered the angel that talked with me with good words and comfortable words.  So the angel that communed with me said unto me, Cry thou, saying, Thus saith the Lord of hosts; I am jealous for Jerusalem and for Zion with a great jealousy.  Therefore thus saith the Lord ; I am returned to Jerusalem with mercies: my house shall be built in it, saith the Lord of hosts, and a line shall be stretched forth upon Jerusalem.  Cry yet, saying, Thus saith the Lord of hosts; My cities through prosperity shall yet be spread abroad; and the Lord shall yet comfort Zion, and shall yet choose Jerusalem.
Zechariah 8:1-3 KJV
 Again the word of the Lord of hosts came to me , saying,  Thus saith the Lord of hosts; I was jealous for Zion with great jealousy, and I was jealous for her with great fury.  Thus saith the Lord ; I am returned unto Zion, and will dwell in the midst of Jerusalem: and Jerusalem shall be called a city of truth; and the mountain of the Lord of hosts the holy mountain.
The first passage is part of a vision Zechariah received in the "second year of Darius" (chapter 1:7). The second passage is part of a prophecy God gave to Zechariah in the "fourth year of Darius" (chapter 7:1). However, in the second passage, God repeats the same words he spoke in the vision he gave to Zechariah two year prior (i.e Zechariah 1:14,16 & Zechariah 8: 1-3). It seems that chapters 1-6 are visions given to Zechariah in the 2nd year of Darius. The book then fast forwards 2 years where he is then not prophesying in visions, with an angel mediating with him and God (Zechariah 1:13, 14), but directly from God: it is Zechariah speaking to the people, not God in the vision to Zechariah.
In context, is there any way of interpreting the visions of Zechariah in the second year of Darius (i.e chapters 1-6) as visions of things to come (e.g "I am returned to Jerusalem with mercies" 1:16) and his prophecy in Darius' fourth year being the fulfilment of those visions?