Schedule component not dependable

I am trying to set up a simple LoadUI schedule to trigger my SoapUI runner (via a fixed rate generator) to generate triggers during all "typical" week day work hours, i.e. Monday - Friday, 8am to 5pm. But I find that when I rearrange the schedules, such as added the next day of the week, or changing the start time, or whatever, that seemingly randomly triggers are no longer generated after I press go.

Further details:
1) All components are "enabled" (i.e. "on")
2) The duration is set to 9 hours for each schedule component (Indicated as seconds): "32400"
3) Start time is set to 8am on each component: "0 0 8"
4) Current TOD when this issue occurs is anywhere between 8am and 5pm - i.e. Within the schedule period.

To fix this and get triggers again sometimes I have to do any one of the following things:
1) Close the project and reopen it (and not changing the test in any way) - now triggers will be generated again
2) -or- Pause 5 or 10 seconds before I press "go" again (and not changing the test in any way)
3) -or- Delete all other schedule components (or connectors) that are not "today", and then re-add them later

Does anyone have any suggestion why this is so flaky? I have searched this forum and did not find anyone else with this issue.

Thanks