The essence of my question is whether anybody's had issues with an iPhone on iOS12 suffering very poor VPN speed on LTE?
iPhone 6s Plus. On iOS10 with the prior generation (v2.x) of OpenVPN, things worked great.
I moved to iOS11, still with the prior generation of OpenVPN. The VPN aspect seemed to work well for me, but the overall phone performance was lackluster enough to motivate me into an update to iOS12.
In a short period of time, I moved my phone to iOS12 and changed my plan type -- still AT&T -- from an ancient to a modern plan. Also the update to iOS12 required me to update OpenVPN to v3.x (3.0.2 -- 894 presently).
The VPN connects quickly, no issues there on both LTE and Wifi. But once connected, I often do not get data access via LTE. The graph shows the Y-axis in BYTES per second. It seems I can sometimes close then reopen OpenVPN and it improves, or switch to airplane mode & back, or reboot the phone...but at best I get a day or two, often only a matter of minutes, where I get data.
I am looking for help to diagnose the issue. I am inclined to believe it's a phone issue, because sometimes it seems to get stuck in some loop where the phone battery drains very quickly while also not providing data access. But when it *does* work, it works like I expect and battery usage is fine. I see nothing odd in the logs when it's burning battery.
I backed up the phone and did a full DFU restore, and for 2 days it was bliss. Now I'm back to the same issues.