We can see such a methodical usage of phonetic characters throughout the documents written in ancient Japanese, and with some exceptions, A-type and B-type were strictly distinguished and there was no confusion between them.
上代の文献では全体にわたってこのように整然たる仮名の使い分けが見られ、一部の例外を除いて甲乙の混同は見られず両者は厳然と区別されていた。