As a Knox partner what actions do I need to take for DA deprecation?

If you are a UEM provider that is managing devices, we recommend that you plan to migrate to the Android Enterprise Device Owner (DO) and Profile Owner (PO) management modes, to take advantage of all new Android Enterprise features which will be rolled out for the AE DO/PO management mode only.

For details, see Google's Android Enterprise Migration Bluebook.

If you are a Solution Partner, for example, a Systems Integrator or Independent Software Vendor, you can continue to call APIs in the Samsung Knox SDK. If you are calling Android DevicePolicyManager APIs, however, you will need to work with the UEM app on the device and request delegation.