Atticus had secretly broken through the expert rank last year, and at the current speed he was advancing, he would advance one more rank by next year.
One of the major things that usually slowed Atticus's progress was his need to train his other powers.
Atticus had far too many bloodline elements and arts to train. He couldn't just absorb mana all day, neglecting these things.
Doing that would make him have a high rank but low battle strength, making it easier for someone of a lower rank to defeat him.
Apart from the fact that he had to train his elements, Atticus still had to do personalized training with Magnus, also shortening his mana absorption time.
But even with all of these distractions, Atticus was still advancing at a faster pace incomparable to others in the human domain.