https://www.theverge.com/circuitbreaker/2017/9/27/16373120/iphone-x-production-issues-face-id-sensors-romeo-juliet-supply-apple-report

There may be even fewer iPhone Xs to go around on November 3rd than the already limited supply that’s expected, due to additional manufacturing issues as reported by The Wall Street Journal.

According to the report, the new facial recognition sensor on the iPhone X is divided into two halves: a “Romeo” module that projects the infrared dots to map faces, and a “Juliet” module that reads the pattern. A source for the WSJ claims that there have been issues with manufacturing yields for the Romeo modules, which apparently took more time to assemble than the Juliet parts. This created a bottleneck that could further limit supply when the phone launches next month.