Maybe you were too quick. The 5GHz band won't come online until about 60 seconds after the 2.4GHz band.
Maybe it could be clearer. "may use" means you may use his utility to restore your settings from backup, but if you don't you will have to re-enter them manually. With this release you cannot use the GUI's "Restore setting (NVRAM)".
I see. Well I'm off to bed for tonight, I will try again later
Thanks for the help !