See the following links
I don’t understand the question. What do you mean by overprovision?
Overprovisioning is when a portion of the total capacity is reserved and not eligable for data storage. This unused space is used by the SSD controller for wear leveling and other functions.
I ask this question and SanDisk has no plans to release a firmware that has 0% over provisoning. The trade off is endurance and performance.