I’ve already communicated with you offline, but as a public record: the version with wired Ethernet module (officially numbered OS 3.2) is a very recent release. Only the recently purchased (like May 2019 and onward) OS 3 controllers are compatible with the Ethernet module, the previous versions use different sets of pins and are not compatible with the module.
I will make an official announcement of OS 3.2 shortly. The short story is that capability wise, it’s the same with all OS 3’s, except it has a cable that can link to a wired Ethernet module (ENC28J60-based). When the Ethernet module is plugged in, the controller functions in wired Ethernet mode; otherwise it’s in WiFi mode. It currently doesn’t support both at the same time, but will function in one or the other depending on whether the module is plugged in or not. Over-the-air firmware update is only supported in WiFi mode (so you can temporarily remove the Ethernet module, update firmware in WiFi mode, then plug in the Ethernet module again). Other than this feature, there is no distinction between OS 3.2 and other OS 3’s. The expanders are the same for all of them.