User blog comment:Jopjopjop/Volume 20 Spoilers/@comment-16281343-20150618134514

Ishibumi made two tweets about v20.

The final battle for the 4th arc will begin in v20. The themes for the upcoming Volumes are "generation change" and "parting".

On his next tweet, he brought focus/attention to Asia. So, most likely she will attain Balance Breaker.