A new feature has quietly appeared in the Google Merchant Center promotions setup, a “Download” option that lets advertisers export detailed information about their specific promotion, including attributes and configuration data.
For now, it seems to serve only as a reference file. You can’t re-upload it or use it as a feed. But this could hint at an upcoming import/export functionality for promotions in the future.

Watch the full video by Emmanuel Flossie here: Google Merchant Center Adds Download Option for Promotions (But Why?)