I´m trying to find out what happens in my system.
I have no scenes nor automations in Smartthings. All my pistons are from WebCOre.
Tried to disable them as well - but everyday at 3.21 a scene/routine turns on all light.
How do I locate the sinner so that I can delete it/modify it?
Hopefully anyone can help me.
Do you use the Classic app or new app? Do you use Alexa or google home?
I do use both of them - but mostly the classic one. But have no scenes nor automations in any of them.
I have alexa at home - when trying to see what starts the routine I can only see that its called daylight - but not were it origins from.
All I can say is go through everything…
Classic:
Routines
Smart lighting
Smart Home Monitor rules possibly
New app:
Automations
Scenes
Alexa:
Routines
Depending on the lights, for example Hue lights using the hub bridge:
Any rules in their apps
Then as you mentioned:
Webcore or other outside apps that you may have
You can go through logs in IDE such as event logs to see if that offers more info.
Not going to be a fun process
Were is the Smart lighting located in the Classic app? Been through all the other but Hue (looking at it right now). But Hue cannot change my smart home status.
So it is your Smart home status and lights that are affected at 3:21 am?
Yes, only message in the app is Daylight is performed. How do I find Smart Lighting?
Did succed into finding a daylight routine in Graphi.smarttings. Deleted it now. Hope it works.
In Classic app, smart lighting is in the Automation tab > SmartApps
But if Smart home status is changing, then you can rule out smart lighting or scenes.
If we are talking arm/disarmed in Home Monitor… are you seeing it in the Classic app or new app? Because they are completely separate apps which will narrow down the cause 
I managed to find it - I found it in Hello Home.
Glad you found it. 
Hello Home (which was from the V1 app!) are routines in the classic V2 app.