No all settings are saved in the database so they are preserved in any update.
That being said it is good practice to always do two things when you make styling changes of before any updates.
Go to Save / Restore and click Save to save a copy of the settings in the database. These can be restored by clicking restore .
Below that click Download ALL settings so you always have a copy of your current settings on your computer.
If you have the “Plus” plugin, go to Appearance > + Xtreme Plus > Save restore, and click Download ALL settings there to keep a local copy of all settings including the plugin.