I'm not sure how you arrived at this 3750 per second number. Processing 1.5 million messages for ⅓ of the time (1500000 messages / 30d / 8h / 60m / 60s) is an

I'm not sure how you arrived at this 3750 per second number. Processing 1.5 million messages for ⅓ of the time (1500000 messages / 30d / 8h / 60m / 60s) is an average of 1.7361 messages per second during those 8 hours per day. If the remaining 500k messages were spread evenly over the remaining 16 hours a day for a month, that's an average of 0.963 messages per second ((((500000 / 30 / 8 / 60 / 60 )×2)+1.7361)/3) over the entire month. Even if you were to process 1.5million messages during the last 8 hours of the month, that is only 52.08 ( 1500000 messages / 8h / 60m / 60s ) messages per second during that 8 hour period.