While recovering iCloud backup... keep going back to the HOLA screen?

I'm currently in the process of reactivating an iPhone with previous iCloud backup.

The iPhone asked me to first update to iOS 9.3.1 (because previous backup on previous iPhone was done under 9.3.1 I guess... (and although this new iPhone showed 9.3.1 !!....)

Now I have gone the HOLA-HELLO screen, entered a wi-fi available, connected with my operator (with proper SIM card of course - phone was working - received test call).

However, now, while it processing with the iCloud backup recovery, when I let the phone go to screen saver, it keeps going back to the HOLA screen... Is this **normal** ? Or should I suspect an issue with this iPhone 5S ?

(Just purchased it from a reseller - it's seller-refurbished, sure source)

Thanks,

Rob