According to people familiar with the matter, Apple is undergoing rare big changes in executives aimed at getting its AI work back on track after months of delays and setbacks. CEO Tim Cook lost confidence in AI head John Giannandrea's ability to execute product development, so he mobilized another executive to help: Mike Rockwell, creator of Vision Pro. Rockwell will be in charge of Siri virtual assistant, who will report to software director Craig Federighi. Apple is preparing to announce employee changes this week.