There are two separate devices on the ER-301 that output the received i2c messages, one for gates and one for cv. Each instance of these devices can be set to output the messages received on one of 100 channels or outputs or however you want to call them. Since the devices are separate and there are 100 outputs for each, there’s technically no need to send both gates and cv values on the same channel/output - they’re not connected in any way.
However, it would probably be less confusing for your users if the two were transmitted on the same output, just so they can select the same output on both devices.
Thomas has done real magic with this update, and knowing his devotion to the platform there is a lot more to explore. What a great way of adding so much value (and now a flexible hands-on experience) to an already great sequencer.