Why should they keep spoilers away from us?
It's all about purposeful timing.
Korean guy by far leaks the earliest, but leaves out tons of info every chapter. This is seemingly on purpose, because he's only give when his source provides him. He also doesn't share pictures anymore. He used to for a couple of chapters, but since 984 he draws them to prevent Shueisha from coming after him.
Redon knows chapter content, but like Korean guy also has a source. He probably is not allowed to leak earlier, to risk losing said source from coming to then. These people are 2nd hand sources countries over to prevent the real leaders from being caught.
There is a window for when everything starts to leak. Generally it's around the time when the issue is shipped to stores around Japan. Redon's summary comes at a point where you can't be sure who in Japan leaks material because many shops receive the issue before the weekend (it officially releases Mondays). This is why a few hours after his summary, LQ raws leak.
Even if those pics were taken days before, they don't leak it until you are more untraceable