Experts have been warning about the impact of the coronavirus on the consumer tech industry, and now it appears that iPhone production has been forced to slow down significantly as factory staff numbers have been reduced.

Apple analyst Ming-Chi Kuo has written a new note for investors explaining what is happening at Apple's main Chinese supply partner (as seen by AppleInsider). Kuo previously lowered his Q1 iPhone production forecast by 10%, and now we know why that may be coming true.

Foxconn's Zhengzhou plant manufactures the iPhone 11 and will also produce the iPhone 9 (aka iPhone SE 2). Kuo claims that only 40-60% of the employees who were there before the Chinese New Year vacation began will return to work this week.

Foxconn's other main factory in Shenzhen, which is not taking an additional week off, has an even lower return rate, which Kuo puts at 30-50%.

As a result, Foxconn has moved some production from these locations to factories in Taiyuan in northern China and India, but these are much smaller than the main facility, so production delays are very likely.

Pegatron, another Apple supplier, has been back at work since February 3. The Shanghai factory, where the iPhone 11 was manufactured and where the iPhone 12 is reportedly being developed, now has a large number of returning employees (90%). However, Kuo estimates that many employees will resign once they receive their February paychecks, leaving Pegatron with about 60-70% of its original workforce.

Pegatron also has a location in Kunshan, where the iPhone SE 2 is manufactured, and was scheduled to return on February 10, but apparently will not. Kuo estimates that even if it reopens, only 40-60% of its employees will return.

If you want to know more about Apple's upcoming 2020 phones, read our iPhone SE 2 and iPhone 12 rumor hub.