User blog comment:Tema19867/Breaking News: 48-hour Summer Camp Island marathon/@comment-2601:601:100:3BAB:907A:36C2:D4C8:F5CF-20180629183033/@comment-7866392-20180630044527

... because that's just when it's going to air. Last week (June 23rd) was Episode 4, this week (June 30th) will be Episode 5, and next week (July 7th) will be the last episode.

Toonamifan55 already pointed out that all of [adult swim], including Toonami, will air as normal on July 7th, regardless of the Summer Camp Island marathon. I don't know why you needed to ask this when he already mentioned it below.