When I picked up my X back in Feb, there was already an impending software update flagged up on the dash as I drove it away and it updated at home that evening on my home wifi. I guess they simply don't bother to update and just leave updates to happen as and when they are pushed over the air. That sort of makes sense as it's one less thing on their delivery prep list.
It was the same story at the first routine service. I got no software update even though there was a newer version available at the time. A few days later I got the update OTA, so no worries.