You should be able to do this in 2 steps, upgrade to 5.7.5.13 and then to 8.1. Here is the documentation on upgrading -https://documentation.concrete5.org/developers/installation/upgradin...

Thank you very much!

Although it's always good practice to keep a website updated, you don't _need_ to rush to update to v8+ unless you have a feature or package you are really wanting to use.

Concrete5 has a very strong history of security (and not being a big target), so in practical terms you won't be missing some critical security fix.

I'd suggest updating to the latest 5.7.x version and leaving the 8+ update until a later date. Also look for updates to the installed theme package. If you've only got one package installed I'd find it unlikely that you'll hit problems.

What you should do is take a full backup of the site and set it up locally (or on another server), then do your test upgrades there. If all goes well, you can then repeat on the live, having your site files and database backup ready to swap back in if something goes wrong.

It's primarily the database backup that is critical to take, as concrete5 updates really only swap over the one big concrete folder where the 'core' is. (but it's always prudent to have a full 'snapshot' of a site in case you delete something, etc)

Thank you for this information!

Going to move their current files over to my server and do the updating.

We'll see how it goes.