The first seven weeks of Daniel’s 70 week prophesy

I understand how Daniel’s prophesy of 69 weeks until “Messiah the Prince” has been fulfilled (Daniel 9:25), but I have a question about the first seven weeks of his prophesy. Was Jerusalem rebuilt in exactly 49 years (7 weeks) from the decree? Or, was it “completed” in much less time, as most timelines seem to indicate? Thank you.