Again there was a day when the sons of God same to present themselves before the Lord, and Satan came also among them. There is no "again" in the original. The words used are an exact repetition of those contained in Job 2:6 of Job 1:1-22.
But they mark, no doubt, a second occasion on which the angelic host came to present themselves before the throne of God, and Satan came with them. To present himself before the Lord. These words are additional to those used in the former passage.
We may gather from them, that, whereas on the former occasion Satan came only to observe, and with no intention of drawing God's special attention to himself, he now had such intention, and looked forward to a colloquy.
He anticipated, doubtless, that the circumstances of Job's probation would be referred to, and he had prepared himself to make answer.