We try our best to stay on the cutting edge here at ChannelApe therefore our brand new eBay channel utilizes eBay’s new REST APIs. Unfortunately eBay has not yet added a way for listings created manually or through one of its older APIs to be updated using the new eBay API. eBay plans to add listing migration functionality but is not yet available. Our new integration works best by creating new listings for your account linked by SKU to one of your ChannelApe variants.
If you need to update existing listings though our Custom Services team might be able to help.