What do you need to prepare a Remote Program Increment Planning Meeting?

On the 3rd of March 2020, we supposed to start a new Program Increment with a client I was coaching. A decision was taken on short notice — just one day before the PI planning. Back at the beginning of March 2020, little we knew that two weeks down the line, the entire planet would work remotely, and in less than a month, more than 2.6 billion people would be under lockdown.