Yes, it’s a somewhat random problem. Turning the power off completely to the bulb does seem to make the problem occur more often, but it can occur even when the power has not been cut. It’s just a random issue where it seems to forget what network it belongs to. Not all bulbs, not all the time, but often enough to be annoying.
We have eight of the GE links and we have the problem two or three times a month. Not always the same bulb, not always the same fixture. Just random.
Yes, we keep the smartbulbs always powered. We mostly use echo for light control so it’s no big deal, although we also have a couple of the Phillips dimmer switches. Eight Link bulbs, every month two or three incidents where they lose connection.