EC2 in-place deployment with cross-zone routing disabled in NLB

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We have an ASG with 100+ hosts in us-east-1, that is distributed across all 6 Availability Zones. This ASG is added as a target group to our Network Load Balancer which is also enabled in all 6 AZs. Currently, we have Cross-Zone Load Balancing enabled in our NLB, which distributes the incoming traffic to all the hosts across all AZs equally. But, this cross-zone load balancing is adding a significant cost to our monthly bills. All our clients connect to our service through VPC peering (private links) and all these clients are also distributed equally across all AZs. From a networking stand point, we don't see a necessity to enable cross-zone load balancing and so we are planning to turn this feature off in our prod environments.

We went through the following AWS docs (1) & (2), and understood that EC2 ASGs by default, will try to maintain an equivalent number of hosts across all AZs to the maximum extent, while adding hosts to ASGs or when a scale-in event occurs. We would like to understand how the following scenario would work with cross-zone load balancing disabled and if it poses any availability risk to our service.

We use "In-Place" deployment type in our CodeDeploy's deployment groups. While hosts are being de-registered from NLB during in-place deployments, will CodeDeploy ensure that hosts are taken down evenly across all AZs?

[Our deployment configuration makes sure that at-least 70% of the hosts are healthy during the course of deployment. Could there be a case where CodeDeploy takes down more number of hosts (or all 30% of hosts) from a single AZ, putting the availability of NLB node in that AZ at risk (since cross-zone routing is turned-off)?]

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