All sounds good. Originally I used to call BA in the country of departure, then for a while they had a RTW desk in the UK, but today you need to find the right agent to get through the process. It is correct that they priced in NOK although as you used an Amex I hope they put it through into GBP (with a decent conversion rate) and you didn’t end up paying Amex’s extortionate international transaction fee - 3% if I remember correctly. It’s the one thing that puts me off using Amex for my international travel.