Now you must be kidding me, Goldie. The Windrush story was bubbling under for years in The Voice (sadly not as influential as the Jewish Chronicle), but the BBC never picked up on it until first the Guardian and then other mainstream media reported it. Even then, there wasn't anything like the concerted campaign that there has been against Corbyn. If there had been, it would have been May that was forced to resign, not Rudd.
The BBC wasn't any slower on Windrush than any other mainstream media, Strolls. A senior minister goes and it gets put right. Compare that with Corbyn. He simply denies there's a problem and won't discuss it until he's forced to. In fact, there's an article in the Guardian today where he blames Jewish leaders for overreacting! You must see that were there is clear racism, and a party leader refuses to address it, the pressure simply grows. It doesn't just fade and go away.