Saaptahik IPL, featuring Sunandan Lele - Part 4: What has led to IPL bubble being breached?

Two of the eight team - Kolkata Knight Riders and Chennai Super Kings - have confirmed COVID-19 cases in IPL's biosecure bubble. What may caused the breach of the bio-bubble? Will it lead to IPL's suspension? Had it not been for the pandemic, would David Warner have continued after being sacked as the Sunrisers Hyderabad captain?