User blog comment:Xilinoc/Ch. 542 - THE BLADE IS ME/@comment-10630156-20130620021814/@comment-10630156-20130620233157

My theory is that they will attack the enemies in the Human World before they attack the Soul Society again as the Human World is not really anywhere as defensible as the Soul Society and the targets that are there are of high level (Urahara, Isshin, Maybe Grimmjow and the remaining visored) and would be a real problem if they managed to get to the Soul Society even if they where attacked again. Secondly the Soul Society is already in disarray their is no point to attack again at least not at this point in time. Their are at least Four Captain-level fighters (Isshin,Urahara,Tessai,Love) and a few Lieutenant level-fighters in the Human World (not counting Grimmjow) and I doubt very highly that Yhwach won't want to get rid of this threat soon.

It might be a trap though set by the guard squads if so he'll have to take the bait or risk allowing his enemies to converge.