After adding a new eBay store all listings would need to be downloaded before orders were attempted to be synced. Most users have lots of old inactive eBay listings and it would take a long time to download all the listings.

Active eBay listings are pulled in first and inactive listings download separately. This means that Veeqo can begin pulling down orders from your eBay store while the historic orders and inactive listings are pulled down as well.

For more information on how to setup your eBay store check out This Guide