It looks like Sony could be on the verge of bringing the WH-1000XM5 to market, a successor to the 18-month old WH-1000XM4. According to an FCC listing, the upcoming headphones have a different design than their predecessor, along with a larger battery and fast charging support.
https://www.notebookcheck.net/Sony-WH-1000XM5-takes-a-trip-to-the-FCC-with-a-revised-design-larger-battery-and-fast-charging-support.598859.0.html