I do appreciate your updates through this issue. It helps a LOT to know what activity is going on. ESPECIALLY when the reason WHY is given! The note about throttling errors was nice.
So, what caused the big outage?
Yesterday's outage was related to a DNS issue on Azure and affected services including PowerApps:
Sorry that this had impacted your apps, flows, and more.
Moving this post as it is a separate question about Teams.