That was the time of the revolt bro. In 66 AD, Governor Florus plundered the temple for tax revenue. Kicking off the revolt. In 67 AD Nero sent Vespasian, who took his son Titus with him to Galilee. They began the campaign to put down the revolt there. Of course capturing Josephus. They had made their way down to Jerusalem. However, Nero died during that time 68 AD. So Vespasian, left there and went to Alexandria. Which kicked off the year of the 4 Emperors. Which saw Vespasian as the emperor in 69 AD.
His son Titus of course went back to Judea to put down the revolt that had been going on during this time. He sieged Jerusalem in April of 70 AD and sacked it in September of 70 AD. So the siege was only 5 months long, but the length of the whole revolt would be the longer time frame you gave for the actual siege.
Didn't you read how the soldiers pulled back to Lasich?
They started the seige ramps then....the Romans didn't stop or wander away. One of the initial volleys of fire arrows caught the store rooms for firewood on fire which then caught all of the grain storeroom on fire...so all of their provisions burned up. They spent 3½ years under seige with nothing to eat except each other.
The Jews had a record year of grain and then an overwhelming amount of firewood was brought in for the zylafori festival. The store room doors couldn't close....
The real start of the rebellion was EXACTLY as Jesus said. Effigies of Caesar were put up all over Jerusalem during the night (because the Jews forbade this....because God said not to) and the Romans also put up a Roman Eagle over the gated entrance to the Temple signifying that worshipping God was because of Roman Rule and subject to it.
(Menalaus and his band cut it down and were executed for it)
A few Jews did leave the Temple when too hungry....but first they swallowed a few gold coins. When the Roman soldiers fed them the jews needed to use the bathroom and the soldiers seen the Jews diddling in their feces for the gold coins....so afterwards they hacked every jew surrendering.
Josephus details all of this....and was considered a traitor to the Jews for telling all of this.
The siege lasted essentially 3½ years. Some of the details you relate are accurate as well about the robbing of the Temple....and how the Jews began pelting the soldiers with copper pennies.