The group behind the HDMI standard, HDMI Forum, says that it will detail a new spec release in a press conference on January 6th that will enable "a wide range of higher resolutions and refresh rates." The new capabilities will be "supported with a new cable," according to the HDMI Forum's email to The Verge announcing the presser.

The spec is likely to be HDMI 2.2, as VideoCardz notes. The Forum's email hints at it too, noting that the HDMI Licensing Administrator, which two of the planned speakers at the event represent, is appointed "to license Version 2.2 of the HDMI specification."

HDMI 2.1, which has only ever received lettered revisions since its 2017 introduction, supports 48Gbps bandwidth, up to 120Hz variable refresh rates, and resolutions up to 10240 x 4320. VideoCardz speculates that the updated spec could allow for higher resolutions and framerates without the need for Display Stream Compression.

Whatever the spec brings, that mention of a new cable is a tidy reminder that like USB-C, not all HDMI cables are the same. It seems unlikely that HDMI Forum would change the port itself, so you'll probably be able to use your old ones with the updated spec, and some might even support its higher bandwidth. Still, there's always the chance you need fresh cables to get all of the new capabilities when the time comes.