After spending all day on this, my hosting company offered to restore osTicket to the earlier build (v1.9.8.1) and voila, everything back to normal. So definitely something got messed up with 1.9.9, at least for my account, and killed the email piping rendering the program all but useless. Good to know my hosting company keeps backups and has the know how to be able to do restores like this. Hopefully this disaster was just a fluke and that osTicket updates are in fact tested quite thoroughly and methodically before being sent off. Especially in regards to basic things, like, does email work?