The accepted date of authorship by critical scholars for the visions in Daniel (7-12) is the second century BC (Maccabean revolt 167-3 BC). The reasoning goes that the predictions in chapter 11 regarding the Maccabean revolt are too accurate to be merely coincidental. So, they postulate that the author of Daniel lived during these turbulent times and witnessed the persecution of the Jews by Antiochus Epiphanes and so wrote these "prophecies" (prophecies that were written after the fact) to bolster credibility and then added his own predictions of the end of the Seleucid empire so that people would believe that the end of times is near and that soon the persecution would be over.
The Apocalypse of the Weeks
In line with this reasoning, scholars believe that the Apocalypse of the Weeks in Daniel 9 was written by this anonymous author to reassure his fellow brothers that the end of Gentile sovereignty is near. They believe that the author of Daniel believes himself to stand in the last week (7 years) of the 70 weeks (Sabbatical cycles) or 490 year prophecy, after which the suffering of the Jews is supposed to end according to the author himself, see 9:24-27; 12:9-13. The idea is that since the prophecies up to the time of the author were all fulfilled (since they were after the fact), this will lend credibility to the author's genuine prophecy of the "end of times", which is not too far in the future (less than seven years away). In other words, bible critics believe that the real time of the author is the last week of the 70 week prophecy, which according to them coincides with the period of the Maccabean revolt.
This is how the leading scholar in apocalyptic texts, John J. Collins, explains Daniel 9 in his book The Apocolyptic Imagination, p. 109,
The first seven weeks represent the period “from the going forth of the word to restore and rebuild Jerusalem (at the time of Daniel’s prayer, 9:23) to the coming of an anointed one, a prince (either Zerubbabel or, more probably, Joshua, the first postexilic high priest). Then sixty-two weeks pass virtually without comment. The focus of the prophecy is on the last week, the real time of the author. This is marked by the murder of an anointed one (Onias III, see Macc 4:34) and the profanation of the temple… His main concern is not in speculating on the future but in providing an assurance that the predetermined period of Gentile sovereignty is coming to an end.
The problem with the calculation of the 490 year prophecy
However I find this theory troubling as it doesn’t seem to meet the quota of 490 years as prophesized by Daniel 9 (the calculation seems to be exact, if it isn’t then there is no point in identifying the prince and the time of the profanation of the temple as Collins and others do). The author of Daniel is pretty clear that we are to begin to reckon the 490 years (most critical scholars agree that the author intended a calculation of 490 years or 70 weeks of years) from the time of Cyrus’ edict which is usually dated to around 538 BC, subtract from it 490 years and you will get a date around 50 BC as the “end of times” prophesized by Daniel; this date is well beyond the Maccabean period, and actually coincides with the beginning period of Roman rule! Since the terminus ad quem for the book of Daniel can be no later than 125 BC (evidence from Qumran scrolls), then biblical scholars should be forced to admit that the prophecies in Daniel (at least chapter 9) are genuine and not written after the facts.
In other words, how can critical scholars support their position from Daniel 9 when in fact the text points in the opposite direction and clearly contradicts the idea that the last week of the 490-year prophecy is the real time of the author?