1. An electrostatic printing machine having a plurality of color stations having a method for maintaining a preset toner age in each of said plurality of color stations, comprising: determining a toner age for each of said plurality of color stations; determining if purge while run (PWR) is required based on said toner age for each of said plurality of color stations; defining an area on an unused portion of an imaging frame for a purge patch, said defining includes sizing a plurality of purge patch regions wherein each of said purge patch regions may have a different size; allocating each of said plurality of purge patch regions to at least one color plane from a group of color separations.