Travel restrictions to China because of the coronavirus have come just as Apple Inc's engineers usually jet off to Asia to perfect the production of this fall's new iPhones, former employees and supply chain experts told Reuters.

FILE PHOTO: People wearing protective masks wait for checking their temperature in an Apple Store, in Shanghai, China, as the country is hit by an outbreak of the novel coronavirus, February 21, 2020. REUTERS/Aly Song/File Photo - RC2U7F9YTS3Z