What this means is that instead of a late September release, Apple could instead be forced to release their new iPhones in October. This seems to line up with an earlier report, although that report noted that it could possibly be pushed to November. This is all allegedly due to the coronavirus outbreak that has impacted the way Apple approaches its products.
For example, factories in China were forced to shut down during the early stages of the virus outbreak. Then there are also travel restrictions that have been put into place to prevent the virus from spreading, and as such, it has been reported that Apple’s engineers are unable to fly out to the production facilities to test some of the features like 5G.
That being said, this would not be the first time Apple has delayed the release of an iPhone. With the iPhone X, the handset only launched in November in 2017. The iPhone XR was also similarly delayed where it only reached stores in October 2018. Obviously the report should be taken with a grain of salt for now, but if you were planning to get the 2020 iPhones, you could be in for a wait, and even then supply could be limited.