do you think they will make new music for Yhwach?

I know that he has one for his "younger self" or old man Zangetsu but do you think they will reuse it as an indicator that's him, or do you think they will get a completely new theme because they are technically two different characters. Also, another thing that could happen is they start off with the old and then add more into the original piece as his new theme. idk my brother is a major bleach fan and is in love with Shiro Sagetsu and we were showing my mother the music while discussing theories lol