There is no direct command to suppress bars. I can think of two solutions:
-After the 5 minutes have passed, skip all bars until the next hour: Bar += 60/BarPeriod. This is a hack and I don't know if it works, but you can try it.
- Produce a special history that only contains the first 5 minutes of any day, and afterwards only one bar per hour. That's normally the best solution since it saves memory.