You are not going to be able to control what firmware you get, nor when you get it, on your specific car. Just because someone else got X doesnt mean you are going to get X soon. There will be firmware versions that you dont even get (its common for cars to skip versions actually).
If you want to monitor what a representation of the fleet is getting, sign up for teslafi or check some other firmware tracking website.
View the release notes and other metrics for all Tesla vehicle updates.
teslascope.com