I purchased a 4x4 back in February and since machines after mine shipped last week, I assumed they were 2x4s. My 4x4 finally shipped yesterday. But based on your comment, I don’t know if last week’s systems were in fact 2x4s. Their order status page does state that they build them in batches…2x4 then 4x4.
The order status page appears to be having problems. All machines are showing up as “processing” even though mine has now been shipped.