Board Thread:Questions and Answers/@comment-10797017-20130624101208/@comment-10630156-20130708142107

Sternritter M wrote:

The vacancy after Aizen and co. defected could have it's reason, apparently there was no one at captain level who could fill those positions.

That is true and earlier on there was no need to act on it quickly because of the relative peace as for Urahara situation that was most likely planned for some time.

now that they are at war they will look to fill those positions really quickly now I think maybe in the way I was stating above