Ease of DW Focus 1.0.9 upgrade to latest version and PHP compatibility

Hi DesignWall Team,
I was wondering how much work a DW Focus 1.0.9 upgrade to latest version would be in principle (or usually) from being an easy drop in replacement to needing quite a bit of work to get things working again.
I need to upgrade my VPS to at least PHP 8.1 and thought an upgrade might help with that.
Is the latest version compatible?
Also, am I mistaken in thinking that some Bootstrap shortcode support was baked into the Theme?
The site uses Bootstrap 3 shortcodes in 569 places which is something I will need to address, and outside of collapsibles, they seem to work without additional plugins.
Best,
R