What happened

Nio (NIO -0.62%) shares dipped nearly 5% Thursday morning before reversing those losses. The stock recovered and turned positive with a gain of 1.4% as of 10:33 a.m. ET. 

So what

Nio reported its October delivery data on Tuesday and investors have been digesting that information over the last two days. While Nio reported a sharp year-over-year increase in vehicle deliveries last month, it was down from September, and investors are getting more anxious about impacts from continued COVID-19 restrictions in the region. Delivery results from Tesla's Shanghai facility in October might have added to investor concerns today, too. 

Now what

Nio delivered slightly over 10,000 electric vehicles (EVs) in October, a 174% year-over-year increase. But that was still less than the 10,878 shipped in September. There is growing concern over a lull in demand for EVs in China. 

There was already an indication of that when Tesla announced price cuts there late last month. A report from Barron's today that Tesla's China plant shipped about 11,400 fewer of its EVs in October compared to the prior month has only added to investors' anxiety. 

Even with Nio's decent production level in October, there have also been concerns that things could get worse in November. COVID-19 restrictions caused the company to halt production earlier this week at its facilities in the eastern city of Hefei. But production has resumed at those plants, reports Reuters today. That news may help explain the recovery in Nio shares after the initial drop this morning. But investors are likely to stay skittish as the virus-related curtailments remain in focus.