Is this forum the only source of free help/support for this product?
For questions about issues? Pretty much.
Github is more of a place to report reproducible bugs/issues, detailed feature requests, and/or Pull Requests.
If you cannot supply the specific help I requested, why are you replying to this issue? I could really use very specific and well detailed instructions as I'm not very comfortable with DB work.
Typically people who install the software should have basic knowledge on how to use the mysql/mariadb, php, etc. so they may fix bugs/issues/etc. if necessary (after all, this is open source and you're on your own). If you do not know how or just feel uncomfortable running an upgrade we offer Professional Upgrade services. If you're interested in these services please email support[at]osticket.com
If you have any modifications/customizations and they affect the database then you will have to undo all of the mods/cust. in order to proceed with upgrading (when upgrading yourself and with the professional upgrade option).