I think the statement that I have the latest software installed only means that I have INSTALLED all the software that has been downloaded, not that I have downloaded the latest out for my model S built in February. The only time I have seen the statement "latest..." change is after a new version was downloaded and I haven't selected to run the install yet. It then tells me I have a new software ready to install.
I don't see a way to pull a download from Tesla. Software versions seem to be pushed and Tesla decides when to push the version to the car.
When I received the car in March with mfg date of February, it came with a 2019 version at a time when many had earlier built cars already with 2020 version pushed to it as early as January.
All very confusing and the earlier 2019 version that my car came with had many problems. The 12.1 fixed the big ones but I had to wait 2 weeks before that was pushed. The service center just told me, it will come. The two worst issues I had with 2019 was the trunk wouldn't close with the button and the wifi signal was extremely weak forcing me to use my iphone on hotspot right next to the car's antenna to even log on to my wifi at home.
I'm just trying to understand how it all works.