Once the signal went away, I tried restarting and cycling as you described above and as everyone tries to do when in an LTE covered area, nothing came back on after 5:10ish pm. (quitting time?)
When I initially showed 4G connection, I did a speed test right away, nothing fantastic and the test actually timed out. (4.00down and the upload timed out)
after restarting the phone, I was able to get a solid connection and the screenshot above showing the 4G speeds.
I tried to capture a screenshot with Open Signal Maps, but for some reason my phone doesn't like that program and wouldn't let me. On the map screen it showed connected to LTE service.