Upgrade to 8.9.6 from 6.3 – Will that be painful?

Hi

I deployed a site on version 6.3 of the ShopperPress theme and have the CityNews child theme on it. The customer decided she didn’t need online commerce after all but liked the themes. If I upgrade her site to v8.9.6 through FileZilla to her GoDaddy Host, will there be a lot of repairs to do to make the site work with CityNews or even another child theme?

It looks like future upgrades just require a button click on the Overview tab, but I can’t seem to check for updates from the old 6.3 version.

Thanks for any reply. There is a strange login error with the old version of the site referring to lines of code in the theme, and I’m hoping the upgrade will fix it. You can still access the WP dashboard and settings, it’s just a pain.

Mark