is bleach: thousand-year blood war (bleach: sennen kessen-hen) episode 15 filler?

In the past, within the Wörtlich hall of Silbern, Sternritter "B" Jugram Haschwalth sits at the end of a long table across from his fellow Sternritter, where "N" Robert Accutrone questions why they have been ordered to defeat the captains whose Bankai they stole and "K" BG9 points out that the Soldat should be able to handle such powerless Shinigami. In response, Haschwalth asserts that the Shinigami can also have their pride taken and brings up Yhwach's assumption that the captains who have lost their Bankai will use the limited time available to them to compensate by training their other powers.