Overcharging by billing for more than 31 days

I submit my meter readings on 7th of each month. I did this on 7th January 2016. On 11th the meter was read by a Meter Reader. I was then billed for a period of 35 days instead of 31 days. The first ****Wh are charged @ R0.999 +VAT, regardless of how many days in the period. Anything above the ****Wh is billed at the higher rate of R1.6064 +VAT, so of course, the longer that Eskom make the period, the more they can charge the customer.<br> <br> Even though I only used 581 kWh in the 31 days between my readings, I was charged for 66 kWh @ the higher rate. Surely this is dishonest and the first 600 kWh should be pro-rata with the number of days between readings.<br> <br> Surely the way Eskom work their accounts is **********?