why are ranked ques disabled?

Network Operations – 3 minutes ago Ranked Queues are disabled until 05/07/2019 08:00 PDT.

7:00 AM Network Operations — Starting at 05/07/2019 05:30 PDT Ranked Queues will be disabled until 05/07/2019 08:00 PDT. Yesterday at 1:35 PM Network Operations — At 05/07/2019 07:00 PDT the game will be unavailable until 05/07/2019 08:00 PDT.