Much of Daniel's prophecy's have occurred already. Daniel is also the key to the Book of Revelation and Revelation is left unsealed.
Remember too that God does not reckon time as we do.
John 7:1-13
Revelation 22:10-11 And he said unto me,
Seal not the sayings of the prophecy of this book: for the time is at hand. He that is unjust, let him be unjust still: and he which is filthy, let him be filthy still: and he that is righteous, let him be righteous still: and he that is holy, let him be holy still.
Daniel 12:4-9
4 But thou, O Daniel, shut up the words, and seal the book, even to the time of the end: many shall run to and fro, and knowledge shall be increased.
5 Then I Daniel looked, and, behold, there stood other two, the one on this side of the bank of the river, and the other on that side of the bank of the river.
6 And one said to the man clothed in linen, which was upon the waters of the river, How long shall it be to the end of these wonders?
7 And I heard the man clothed in linen, which was upon the waters of the river, when he held up his right hand and his left hand unto heaven, and sware by him that liveth for ever that it shall be for a time, times, and an half; and when he shall have accomplished to scatter the power of the holy people, all these things shall be finished.
8 And I heard, but I understood not: then said I, O my Lord, what shall be the end of these things?
9 And he said, Go thy way, Daniel: for the words are closed up and sealed till the time of the end.
King James Version (KJV)
Public Domain
Source for study.