Update replication settings documentation with NVMe notes

Added notes regarding target region support for NVMe-capable VM SKUs and automatic detection of disk controller updates during replication.

Author: AkshitGureja

articles/site-recovery/azure-to-azure-how-to-enable-replication.md

@@ -48,6 +48,9 @@ Use the following procedure to replicate Azure VMs to another Azure region. As a
 1. In **Replication settings**, you can configure the following settings:
     1. Under **Location and Resource group**,
        - **Target location**: Select the location where your source virtual machine data must be replicated. Depending on the location of selected machines, Site Recovery provides you with the list of suitable target regions. We recommend that you keep the target location the same as the Recovery Services vault location.
+         >[!Note]
+         >If the selected target region does not support an NVMe-capable VM SKU, Azure Site Recovery blocks the enable replication action and would display a validation error before replication starts.
+         >
        - **Target subscription**: Select the target subscription used for disaster recovery. By default, the target subscription will be same as the source subscription.
        - **Target resource group**: Select the resource group to which all your replicated virtual machines belong.
            - By default, Site Recovery creates a new resource group in the target region with an *asr* suffix in the name.
@@ -108,6 +111,9 @@ Use the following procedure to replicate Azure VMs to another Azure region. As a
 
 1.  After the VMs are enabled for replication, you can check the status of VM health under **Replicated items**. The time taken for initial replication depends on various factors such as the disk size, used storage on the disks, etc. Data transfer happens at ~23% of the disk throughput. Initial replication creates a snapshot of the disk and transfers that snapshot.
 
+>[!Tip]
+>In scenarios of a successful migration of disk controller from SCSI to NVMe after replication, Azure Site Recovery automatically detects the controller update and continues replication without interruption. New recovery points generated reflect teh updated NVMe disk controller type.  
+
 ### Enable replication for added disks
 
 If you add disks to an Azure VM for which replication is enabled, the following occurs: