Thank you for the feedback, it’s really good insight to have.
Was the test store you used another Shopify store? Asking because Shopify has since confirmed a sandbox isn’t possible because you need to have a unique store ID to speak to Quickbooks (I’m still not clear this is necessary though, as we already have the file export from QB as provided by our client so as far as I can tell just need the connector app and Stocky).
Based on your experience, it seems inadvisable to connect QB to the test store at all due to avoid complications when wanting to perform migration on the actual production store (existing).
Appreciate the feedback!