I have the exact same issue - using the latest MS Windows 64-bit, Edge, cycles set to 1000, every 5 minutes, it can run for a day, sometimes more, but it will also hang and not auto schedule - I check my progress by clicking the tab and away it goes again - it's been doing this for a long time.
I set my tests for every 5 minutes for 1000 tests - it runs day and night automatically scheduling ever 5 minutes - however, many times it will simply stop scheduling the next cycle - however, if I click on the Edge browser tab it immediately fires off and runs - what is causing this - it typically runs flawlessly, but then it can hang like I mentioned and an entire over-night test period can be lost.