@Mathew James ,
It is generally best practice to deploy pre-production environments in a separate subscription from production environments. This helps to ensure that resources used in pre-production do not impact the resources available to the production environment, and vice versa. Additionally, it allows for better resource management and cost tracking, as resources used in the pre-production environment can be separately billed and accounted for.
That being said, it is also possible to deploy pre-production environments within the same subscription as the production environment, using resource groups to isolate the resources. This can be a useful approach if you want to leverage specific shared resources or infrastructure between the two environments, but it is important to carefully consider the potential impacts on resource availability and cost.
Ultimately, the choice of whether to deploy pre-production environments in a separate subscription or within the same subscription will depend on your specific needs and requirements. It is generally recommended to carefully evaluate your options and choose the approach that best aligns with your overall goals and objectives.
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