The Times of Israel: Netanyahu was warned in advance

They confirm what Abramson reported previously: 

"An Egyptian intelligence official said that Jerusalem had ignored repeated warnings that the Gaza-based terror group was planning 'something big' — which included an apparent direct notice from Cairo’s intelligence minister to the prime minister. [...] In one of the said warnings, Egypt’s Intelligence Minister General Abbas Kamel personally called Netanyahu only 10 days before the massive attack that Gazans were likely to do 'something unusual, a terrible operation.'"

Of course Netanyahu denies he ever got such notice, using Trumpler's tactic of calling it fake news. And just like with Trumpler, that denial can be taken as a strong likelihood that it indeed happened. Abramson's hypothesis is looking more and more plausible.