set the max time for 3 days??

That's a bit too long.

I've set it to 6 hours, from 2, so there should be *some* improvement now.

i mean don't make it a set number of hours let it have a variable hours more or less. for example if it's 6 hours, could vary between 5 hours and 40 minutes and 6 hours and 20 minutes.

There is a reason that it is aligned to the time frames it is - the scheduler is more reliable like it is now.