The Device to Device network is always active so if a M1KE is not connected to a Wi-Fi network, then it can RX/TX on any channel. If it is connected to a network, then it can only RX/TX on the currently connected AP's Wi-Fi channel.
If the Multicast Network is enabled (it is enabled by default) at the Broadcast connector settings, then the M1KE will also RX/TX on the currently connected Wi-Fi network using multicast IP packets, so other M1KEs not on the same Wi-Fi channel or SSID but on the same multicast IP network are able to communicate. See the diagram at the bottom of the page: https://manuals.sharkrf.com/m1ke/web/connectors/bcast.html