Thanks Pravin. Support got back to me saying that auto-update is not possible at this time. And their advice is to update manually every couple of days which is absurd. I can't be manually updating over 300 products in 3 days, let alone repeat the process. Anyway, I encountered new problems. I manually updated a 'published' product. But instead of removing the old price, the system retains both the old & the new price (see image). When I saved it, my published product became unpublished and I've gotta do it all over again. Also on another product, the supplier doesn't exist anymore. When I manually updated it, it didn't remove the product from my website. So I had to delete it permanently. Thanks again for your help.