It does the same thing for my 436HP and all that does is make a copy the present profile but once you have the new profile & all of the profile settings!!! (I think that's how it is designed to work).
Once you have the new profile all you have to do is delete the old favorites and pick new freqs from the database & create new favorites... To me it makes sense since you are creating a new peofile for the same radio you would want the same profile setting, right?
If you look closely, you will see there are differences. While still displayed, all Favorites Lists have Download and Monitor Set to Off. Editing the Profile itself you will see the opening screen is generic and just the "xxx Dispatch" Service Types have been turned on.
There are certain fields in a Profile that have to have some values for them for "things" to work, so Sentinel will populate them with something/anything.
And yeah, never ever delete a Favorites List unless you are absolutely, positively certain you will not have any use for it in any scanner. And then seriously consider exporting it to an HPE file before you delete, just in case you change you mind. After all, you created that Favorites List for some reason.