Your schedule is 10am to 5pm(EST), but in your In Queue Call Flow you can define through "DECISION" and using the expression editor something like this :
if(Hour(Flow.StartDateTimeUtc)-4 > 9) or if(Hour(Flow.StartDateTimeUtc)-4 < 16)
On TRUE , you have to add "CREATE CALLBACK"
On FALSE , add "Music On Hold" or "Play Prompt"
just to reduce the number of callbacks and you should be able to recall all daily callbacks within the business hours.
or also , in order to reduce number of callbacks,you can offer callbacks only if "ESTIMATED WAIT TIME" > 180 seconds or after 180 seconds wating in queue, for instance.
Do you have any triggers when you offer a callback?
Let me know
Stefano