Upgrading from 15.2 to 17.1

Hi all.
I just tried upgrading from 15.2 to 17.1 and got the seemingly endless “migrating” message.
I’ve read many a post regarding this and was unable to get past this initial screen so I restored from a recent back-up and am back at 15.2.

I’m running Aeon MQ6 and I’d like to upgrade to Kodi 17 but I’d like to keep all my current settings.
Must I upgrade to 16 first or should an upgrade from 15.2 to 17.1 be possible?

Is there one particular issue causing the “migrating” message to continue?

Thanks.