I took delivery of a Model X in early May, and got a software update within a day or two. It had been on a 2022.x.101.y release, and went to I think 2022.12.3.2, and then a week or two later IIRC 2022.12.3.16 (I’ve now received the beta).

I don’t know what to say other than make sure you set up WiFi, park overnight where you get a WiFi signal, and set your software preference to Advanced in the in-car UI. I hear you can request a service appointment where you ask them to push a software update and they can do it (not the beta but a regular software update), but I haven’t done that myself.