Hi James,
Many thanks for your reply, we haven't submitted our feed to Google Shopping, this is done automatically by eBay.
Do you think this could be why? I'll give this a try this week / look into how to do this.
Also, we haven't changed our store name/ URL. We've contact support on both ends, and searched around for solutions but all come back to the same conclusion. All resources seem to of run dry. Both eBay and Google say it's not their issue, as others have mentioned. - Which is helpful.