The work for providing updated solutions to work without ACS is ongoing, and the team will have a solution prior to the Nov 7 deadline.
For those using Enterprise Portal, you can find the required KB available today. See KB 4133646
For those using WorkflowApprovals, this work is nearing completion. Monitor this blog post and an update will be provide soon with an update. An updated Mobile connector will need to be installed, and new configuration will need to be done to create a new service bus and configure SAS.
For those using Timesheet or Expense mobile, there will be updates across the mobile connector, Azure configuration, and apps that are required. This work is still ongoing and we’ll have a dedicated post and updated documentation to help with setup of the new solution prior to the Nov 7 date.