In 9800 WLC, you might have observed that although 6 GHz band in US domain supports 320 MHz until channel 221 there is no option to configure this from the WLC webGUI. The last channel that the webGUI will allow us to set for 320 MHz is 189.
6 GHz band in mode 2 supports 320 MHz channel width for higher channels above 189 with center channel index as 191.
Although this cannot be configured from the webGUI, it can be configured from the CLI as follows-
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