Scheduled interval

package main

import (
    "fmt"
    "time"
)

func main() {
    interval := 4 * time.Hour
    now := time.Now().UTC()
    offset := now.UnixNano() % int64(interval)
    pastTime := now.Add(-time.Duration(offset))
    futureTime := now.Add(interval - time.Duration(offset))

    fmt.Println(pastTime)
    fmt.Println(futureTime)
}