The Filter node keeps the item instead of discarding when the condition is false.
You should use the IF node for such type of comparison.
Then the true output is “before 8am,” false is “8am or later.”
You misunderstood the Filter node… is not like what you think is comparinh the time … it evaluates the whole expression, and always will be false.
If you want to keep the Filter node :
Set Data type: Date & Time
Operation: is before
Left value (Field):
{{ new Date($json.timestamp) }}
Right value (Value):
{{ new Date(new Date().setHours(8, 0, 0, 0)) }}
This way the Filter node does:
“left date is before right date”
and will keep only items with timestamp < 08:00.