Not sure if this is doable, but...

[Mamorien]

Technically midsummer in 2017 was the 21st, or the 20th at 11:25PM EDT.  That's close enough in my summery judgement.

Thanks. 

How many characters are the core protagonists of Bleach these days, 500?

I don't know how many of the cast Kubotite himself considers "core protagonists" (he might not either), but in my opion, it's ultimately Ichigo's story in the same way Sandman was ultimately Tall, Pale and Interesting's story. Even in chapters taking place before Ichigo was born, he's at most one degree of separation removed from the people involved.

("Quit answering rhetorical questions, you'll screw up my rhythm.") The core group I had in mind was Ichigo, Rukia, and some subset of their friends and family -- definitely to include Orihime and Renji,

and some spoilers for the last cour of TYBW.

and, since I was planning to bring everyone in from Chapter 686, Kazui and Ichika. (And Kon as Kazui's minder and comfort object, per the "Howl from the Jaws of Hell" chapter.)

My plan in the TNB days, as per this Attic post, was to have them accompanied by the other people who were present in the Kurosaki living room to watch Chad's title bout, with Chad and Uryū part of a separate group of "Karakura All-Stars" which I can't find my notes about, but I'm guessing it also consisted of basically the Urahara Shop staff plus maybe Isshin. My current intention has Chad and Uryū arriving in closer proximity to "Team Deathberry" (as I called them in other posts), brought together by the winds of ka, or the Ultimate Force, or whatever in-story manifestation of narrative convenience best fits. I haven't decided where the twins, and Ichigo's human friends, wind up or when.