diamonddog wroteI received a response stating that the issue is on my VPN provider's end (Mullvad), but I'm not sure if that's correct. Using the current public OpenVPN Connect app on multiple devices of mine running iOS 11.4.1, I'm having no problems at all. Same exact Mullvad configuration files and everything.
I agree. Mine are the exact same ones I use on Windows, on another iPhone on iOS 11.4, and on this iPhone on iOS 12 but with the live version of OpenVPN Connect. On Windows and iOS 11 they work perfectly fine, and on iOS 12 with the live version of OpenVPN Connect it works at least part of the time, so I don't see how it's something other than OpenVPN Connect.
Also important to note is that mine are for 3 different providers.. All of them break exactly when I use OpenVPN the 3.0.. But yeah, it's not OpenVPN Connect, it's them.........