One click automatic delegate means you only need set up once, specified portion of your daily reward will be delegated to a chosen node automatically.
You can cancel your automatically delegate at anytime and it will be in effect immediately.
There are 4, and they are 50%, 66%，88% and 100%. Once you set the automatically delegate, system will allocate the chosen percentage of your daily reward into delegate.
A validator node can only automatically delegate to itself.
If you set it up before 24:00 UTC+8 time, it will be in effect the same day.