The more research I do the more I see this as a large problem. We've grown and need to re-think our SKU generation strategy. The problem is, we have no way of making bulk SKU changes. We've been advised by DEAR that the only way to change SKUs is to click into each product details page and change it manually.
The simple solution is to add a new column to the Inventory List Export which has the ProductID (which is unchangeable and independent of the SKU). This simple change would allow any changes to the SKU field for any product.
As a developer by trade, I know it would be possible to implement this (and probably quite simple). Even if you're using a NoSQL DB this shouldn't be difficult. I can see a unique ID (separate from the SKU) is generated for each product because it is exposed in the URL and network request (ProductID vs ProductCode):
I think that this feature, while small in nature, would be a huge convenience for your customers and could help you keep the large ones as they grow. As long as DEAR is improving and moving in the right direction I will continue to support and recommend your product. Thank you for your hard work.