Is it possible to update my existing Multi-Channel Cable Node and/or Fan Node with an over-the-air update to make it compatible with the CO2 sensor?

No. As mentioned previously, the changes to the Multi-Channel Cable Node (CN08) and Fan Node (FN) are not strictly firmware updates. There were hardware changes necessary as well. Because of this an over-the-air firmware update is not sufficient to make this existing hardware compatible and able to read the Grain Quality Sensor (CO2). Multi-Channel Cable and Fan Nodes shipped prior to June 16, 2023, will need to be replaced with new hardware.

Note: Any new Multi-Channel Cable, Fan Node or Fan Node Radio shipped on June 16, 2023, or purchased after that date will be CO2 compatible and will continue to receive over-the-air firmware updates to remain compatible and up-to-date moving forward.