Hi Claire,
Sure, it’s a great question. I think our article on How is the "Annual production this year to date" figure shown on the duty page produced? should cover your question on the impact of the duty settings. Based on my understanding of your second point, I think you want to set your customer in those circumstances as a partner brewery is liable for the duty (brewed under their license), it will then not count towards your duty return. However, you can still view your production figures on the beer duty pageas here you can see what has been produced In house and offsite under your license and under another business licence, as shown in the screenshot below.
I hope this answers your question, but let us know if you need any more support at all.