An index is maintained to relate fitment from the Google doc with products from the store catalog. This index is updated automatically during off house every night, Eastern Standard Time.
You can manually re-index the product catalog and fitment sheet if required from the dashboard that will be provided after setup is complete
Sync Product Catalog will add, update and remove any changes updated within the BigCommerce catalog, such as new products, product names, pricing, and collection assignments.
Sync Google Sheet will add, update and remove any fitment updates made within the connect Google Sheet.