Hello,
Thank you for posting your query in Microsoft Community.
We do understand your concern and we will be happy to help you regarding this.
I would like to inform that as of now Windows 10 official upgrade is not available for Lumia 1320.
I hope this helps you. If you have any further queries, feel free to contact us. We will be happy to help you.
Thank you.
So if this update is not a option for a lumia 1320 phone AND microsoft instead of just only ending support but also SHUT DOWN back up and restore lumia 1320 with win 8.1 option, how can we back up and restore EVERYTHING on our own phones?! With a pc?!