I did a clean install from the nightly and things seem to be working. I haven't yet reinstalled TVHeadend since I only have the one tuner device and its on the RPi3 and I haven't seen the "remote communications server failed to start" message again so I'm suspecting its TVHeadend that's causing it.
What versions of LE did you tried? Did you tried to change the "Wait for network before starting Kodi" in LibreELEC settings?
I don't know if what I experienced is the same.... Where I live probably because of old electrical grid, sometime we have 1 second power down. Sometimes 1-2 per day, sometimes without a single power down in a month. So, I had some kind of network issues after the short power down. Mostly with TVheadend, but in that case the weather app was not functional too. After a reboot always was functional again. That was when I used the LE 10.0.2 (3x RPi3). Tried to switch to Le11 nightly, increased the "wait-for-network" time (from 10 sec. to 120) in LibreElec settings. I think was something when the router wasn't back yet and the LE don't wait enough for network (?). Now I'm using the LE 10.0.3 stable with increased "wait-for-network" and looks like without network issue...
Just in the case if any of these information useful for you...