I asked for the model numbers because that’s what matters for troubleshooting. Just as an example, the GE switches and the Schlage locks come in both Zigbee and zwave models. Each can get glitchy, but for different reasons. 
So especially when asking for troubleshooting help on the internet in the future please give specific model numbers.
That said, you have enough variety in your setup that it doesn’t look like a protocol issue.
Most likely either SmartThings platform glitches, delayed automations, or Alexa hunches.
Alexa hunches are easiest to troubleshoot, so I’d start by looking there.
I’m not feeling well this morning so I’ll leave it to others to answer questions on that, but here’s a good thread, with a lot of details from someone who got hit by the problem:
https://community.smartthings.com/t/help-my-smart-switches-all-turn-off-at-1am/