While I have no solid evidence (speculation), I would imagine that Disney looking really good (for the first time in several months) due to Little Mermaid might have put the announcement off a few days. That, as well as all of the regional re-openings and new attractions, might make Uni want to be sure that it has the winning hand on the chosen week.
I also think that HHN makes for a great distraction in the case of any Pride news that might cause inevitable political turmoil. Disney always announces two or three things at a time (Starcruiser; New Ariel; Massive Layoffs) as a sort of "compliment sandwich", so I wonder if Universal is anticipating some bad news in the next few weeks that they can sweeten with HHN news.
EDIT: My prediction is Villain-Con has some major issues, and that it's opening way later in the summer than anticipated. They'll announce an Early September release date along with a big HHN update. They'll delay it as long as possible, and maybe open the Minion Cafe the week afterwards, to make a good news sandwich.