Is EES required every three years?

Is it true that our records will be kept for three years? Does it mean we have to re-register from scratch again then? 

The EU states that EES database entries of personal and biometric data will be saved and will remain valid for three years from the date of the person’s last exit from the Schengen area. 

One of the large cross-Channel transport companies told us they understand the ‘full’ EES registration process will not therefore have to be completed again unless the person is away from the area for three years.