This is because according to a recent FCC sighting, it appears that Sony could have a new version of the headphones in the works. The latest model is the Sony WH1000XM3, so barring any changes to the model number and name and based on the FCC filing, it has revealed that the next model will be known as the WH1000XM4.
Exactly what kind of changes Sony has made to the headphones remains to be seen. The headphones in its current form offers up noise-cancelling features and also gesture controls, where users can swipe gestures on the earcups to control media playback. Users can even tap on the earcups to disable the noise-cancelling feature so they can have brief conversations with those around them.
There is no word on when the WH1000XM4 headphones will be launched, but with CES 2020 taking place in the next few weeks, we might not have to wait too long to find out.