Short version, it didn't help.
I tried turning off the steady ping while still at 4.0.16.
Attempted the auto update to 4.0.18(?) and it failed. admin page was unresponsive but the router functioned for the day while i was at work.
Rebooted. Tried the steady ping again, no luck. Turned it back on.
Upgraded to the 4.0.20 firmware. Still no luck, with steady ping on and off.
Changed the connected to wired and it showed up right away in the app.
While on wireless I couldn't ping the TV from my laptop but it resolve the name.
Once wired again, ping worked.