Can I stop order confirmations going out per shipping address in a multiple shipping order?
Yes, this is an option that you can turn on/off in your Giftship dashboard.
From your home Shopify dashboard, go to Apps –> Giftship –> Edit Settings and scroll down to the Shipping to Multiple Addresses section. From here you will see the following option:
To prevent Order confirmations going out per shipping addresses, check “Disable notifications for follow up orders?”.