翻译问题

half

下面是Exetel Naked ADSL关于超量使用收费的说明，俺红字部分理解得对不？
12 noon to 12 midnight : I don't want to be charged when I reach my peak download allowance and realise my download speed will be reduced to 64 kbps once that allowance is reached and if I exceed my limit by more than 2 gbytes I will be charged at a rate of $6.00 per gb or part thereof until the end of the month.
红字部分：如果流量超过2gbytes，按照6刀/gbyte收费。
12 midnight to 12 noon: : I don't want to be charged when I reach my off peak download allowance and realise my download speed will be reduced to 64 kbps once that allowance is reached and if I then exceed 56 gbytes in this period I will be charged at a rate of $6.00 per gb or part thereof until the end of the month.
红字部分：如果流量超过56gbytes，按照6刀/gbyte收费。

naughtybaby

1. 超出高峰期最大流量2gb,  至本月底每gb按6刀或6刀的一部分收费.
2. 超出非高峰期最大流量56gb, 至本月底每gb按6刀或6刀的一部分收费.

按6刀的一部分收费我猜是因为你流量不会正好是整数. 比如5.5gb, 那0.5部分就按比例来收费.