How is ADDS protected against entire region failure?

Hi,
I'm developing a DR strategy for my primary region.

The strategy I am taking is to use Azure Site Recovery to restore VMs to my paired region. This is all great if the ADDS in my primary region is still available and I can connect to it so that ASR can join the restored VMs to my domain. What happens if I lose the entire primary region where my ADDS resides? How can I protect myself so that I have ADDS available to join machines to in the paired region? I see from the ADDS FAQ that ADDS can only be attached to one V-Net. Can someone give me some ideas as to what to do about ADDS so that it remains available to my paired region if the primary region is lost?