Installing Dove upgrade

I’m helping a friend with wordpress. He bought dove wordpress theme some years ago and i will update the dove theme wich i downloaded from themeforest.

In update instruction it says that first delete the dove theme, then update by uploading the zip file.
Is this correct? What happens if i first delete dove theme, will the site function?
or can i upload the zip file to overwrite existing dove theme, is this safe?

If your friend is using very old version then may be not safe (compatibility issues, upgrade functionality issues). Will be better tell your friend to ask it to the theme author with mentioning current theme version. Thanks

Installed dove theme is version 1.0 and i will install version 1.1.6.

Which way is the safest way to do install?

  1. upload zip-file overwriting existing dove version?
  2. delete dove theme, uploading zip file with version 1.1.6?

The theme author can tell you the best because theme Author are best expert about their theme functionality.