These are new bulk mutations for the Skio API—addSubscriptionLineBulk and updateSubscriptionLineBulk. We added them to handle multiple subscription line changes in a single API request. Instead of aliasing multiple mutations manually or making dozens of individual calls, you can now batch line item additions and updates. This is built for developers and technical teams who need to programmatically modify subscriptions at scale—like adding products to hundreds of subscriptions during a promo or updating pricing across your subscriber base. Faster processing, cleaner code, fewer API calls.