is bleach: thousand-year blood war (bleach: sennen kessen-hen) episode 31 filler?

's body slams into the Shakonmaku and begins dripping inside. In the Greater Soul King Palace, a kneeling Yhwach's body ripples before darkness surges out of it and across the floor, past his Schutzstaffel, to erupt from the bottom of the structure and hurtle downward.

Simultaneously, within Kisuke Urahara's laboratory in the replaced Seireitei, alarm bells ring and warnings flash on the screen while the Shinigami inside learn that a massive Reiatsu is approaching from above. Seconds later, the dark mass slams into the Shakonmaku with enough force to shake the entire city and begins dripping through the hole on one side.