Both your drawdown and cash balance will be carried forward when you are billed again.

It is not reset each month.

However, if your account is in a failed status as of close of market prior to the renewal, we will reset it for free.

You can reset your account at any time and start over, whether you have failed an evaluation or simply want to reset. You can reset as many times as you wish. 

This video explains how to do resets.