Sorry Mike for the vague explanation. After I logged into osTicket I was automatically presented with a page to run osTicket Upgrader. The upgrader applied the database patches needed (27 to be exact) All the data was available to me after the upgrade. I have since been configuring version 1.15.2 to create tickets from emails, creating new departments, adding filters etc. All old tickets, agents and users were present. I'm just glad that I didn't have to create from scratch.
Hope this helps.
Denise