Hi @RameshMukka,
You could following steps to approach that:
1. Since the item modified time is UTC time, so you should use the convertTimeZone() function convert the utc time to your local time.
convertTimeZone(triggerOutputs()?['body/Modified'], 'UTC', 'Pacific Standard Time','yyyy-MM-ddTHH:mm:ss')
2. Use Condition action check if the time greater than 18:00 and less than 24:00:00, if yes, add 1 day, then convert it to the UTC time, the time set to 8 o'clock, and append it to the Delay Until action;
addDays(variables('LocalTime'),1,'yyyy-MM-ddT08:00:00Z')
convertToUtc(formatDateTime(outputs('Compose'),'yyyy-MM-ddTHH:mm:ss'),'Pacific Standard Time','yyyy-MM-ddTHH:MM:ssZ')
3. if no, convert the time to 8 o'clock, and append the time to Delay Until:
convertToUtc(formatDateTime(variables('LocalTime'),'yyyy-MM-ddT08:mm:ss'),'Pacific Standard Time','yyyy-MM-ddTHH:MM:ssZ')


Best Regards,
Community Support Team _ Lin Tu
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