Another bit of hard learned knowledge by us on upgrading for many years here :
We strongly recommend you avail yourself of Softaculous abilities to allow you to clone your existing installation and then try running upgrade (in order, don't skip) . Softaculous also allows you to make a complete backup files and DB that can very easily restore to your original.
Additionally Softaculous now has staging - which allows you to test any new changes and if you determine they work then the staging will import the changes into your live site.
In all of these upgrading, cloning, or staging we highly recommend you make a backup of your live site, place your live site into Mtce mode, then run the upgrade or apply the staging. See if your newly amended live site has taken the changes well. If so take your MTCE mode off. if not you can restore from your backup and you will be back to where you were prior to attempting changes.
Regards
The Support Team
We Hear You 2, Inc. (WHY2)