Final answer:
The duration for which personnel must deploy before being authorized to wear special mission low-profile civilian clothing is not provided in the information available. One would need to check specific military regulations or consult with a military expert for accurate details.
Step-by-step explanation:
The issue of special mission low-profile civilian clothing is typically handled under specific guidelines regarding military personnel's attire during deployment. The exact policies can vary depending on the branch of the military and the nature of the mission. Given the background information provided, the answer to how long personnel must deploy before being authorized to wear special mission low-profile civilian clothing isn't explicitly stated. However, the information discusses various aspects of military personnel on deployment or service, such as changes to drill requirements and policies during prior conflicts, which suggests that such decisions would be based on operational security measures and regulations specific to each situation.
Hence, one may need to refer to specific military regulations or contact a military legal or personnel expert to get the accurate duration required for the authorization of special mission low-profile civilian clothing for deployment.