Hi @Qwertyqwerty1, let me see if i can help out here! 
If you have more than one update to install until you are the latest available version, you will get a new notification after each update saying that there is a new update available. If you have many updates pending, which can happen if you have bought an Xperia device that is not completely new.
You can either install them one by one, and restart your device after every update, or you can perform a software repair using Xperia Companion and your device will get the latest update at once. Please not though that a software repair will erase all user data, so make sure to do a backup of your phone before proceeding with the repair.
I hope this answered your question. Please get back to me if I have misinterpreted your question.
0online
1899314posts