Microsoft first announced that it was releasing the Windows 10 Team 2020 Update back in October, but that plan hasn't gone so well. It ended up pulling back on the update, re-releasing it in January for the Surface Hub 2S as a phased rollout.
It started rolling out for the original Surface Hub a couple of weeks ago, and now, Microsoft is pulling back again. The company was set to release it globally on March 2, after releasing it in some regions on February 24, but it's throttling the update because it has to investigate a known issue. Also, the U.S. release is pushed back to March 9.
There are a bunch of known issues on the list, and Microsoft didn't say which one is the one it's investigating. One of them seems pretty serious though, and it's specific to the first-generation Surface Hub. After installing the update, you'll be greeted by a "No bootable device" message, forcing you to re-image the device with the Surface Hub Recovery Tool.
Right now, the schedule only includes devices with full telemetry enabled, so yes, there will be more updates regarding the Windows 10 Team 2020 Update, including for Windows Update for Business and for devices that don't have full telemetry enabled.