Switched to the official LOS version yesterday night, and it seemed to go flawlessly, but I have random reboots every few hours since then. Interestingly, I didn’t have random reboots with the unofficial version.
I have LOS with root and microG (patched with tingle), but reading above, it seems like this configuration works for others? 
Already tried cleaning cache and dalvik-cache of course, but to no avail.
Anyone else with random reboots after migrating?
Edit: Did a factory reset, then reinstalled all apps. Problem seems solved now, not a single random reboot since then. 
2nd Edit: OK, it still does reboot, though less frequently than before.