DNS servers in Azure Local Logical Network can't be changed

In the near future, we want to migrate the Active Directory servers and remove the old subnet. However, we are unable to modify the DNS servers in the Azure Local Logical Networks. It appears that this was possible before. Can this option be added again?

Start by reproducing the inability to edit DNS servers in an Azure Local Logical Network and compare the current behavior with the previously available option. Confirm the expected DNS-change workflow for migrating Active Directory servers and removing the old subnet; done means the DNS servers can be modified and the migration scenario is supported.

Written by the indexing model from the issue text.