I have a Cloud Sync Collection that i use to sync devices from a on-prem WSUS solution to using Intune Update Rings. This very same Cloud Sync collection is also targeted for Feature Update lock to v1909.
What i see now is that in the process of moving a device from on-prem Wsus to Intune Update Ring, there is a delay before these settings from Intune come into effect, and during that time, WU take it up itself to push V2004 for the device.
I can think of a few ways to possible delay/stop this from happening, but what is the best option to do it? use a GPO/ConfigMgr, seperate cloud sync collections, AAD device groups etc??