Yes, Coupon Codes, Promo Codes are part of Promotions. When you move Promotions using StagingPro, StagingPro follows the following steps:
...
As of now all promotions are moved in its entirety. Moving selective promotions will be considered as part of the development roadmap.
IMPORTANT: Be advised that Promotions moved through UI cannot be edited. Workaround is to delete the promotion, recreate it correctly in source and then migrate so it transfers across correctly.
To view our onboarding steps, please access the following article → StagingPro Onboarding