If the original construction permit (the very first one granted after winning the filing window) is not yet constructed, the organization must wait until 18 months after the grant in order to assign the permit to another qualified organization. If the FCC had to use the point system to grant this application (in other words, there were others applicants in the group of mutually exclusive/competing applicants that were dismissed as "non tentative selectees"), then the organization that the permit is assigned to must meet the same or greater number of points. If the construction permit included an involuntary time share provision, then the local presence date of the new organization must be older than the "youngest" organization in the time share group.
Once granted, the assignment must be consummated through the filing of a consummation notice with the FCC to finish the transaction. The new organization will have the remaining time (less than 17 months or so) to finish construction. No extentions will be given past the original 3 year construction period except in extraordinary circumances where tolling would otherwise be permitted.