Canon's 1-Year CarePak Extended Service Plan for the imagePROGRAF iPF655 Printer provides professional warranty coverage which starts the day your regularly-supplied warranty expires.
For the duration of the warranty extension, you'll receive toll-free technical support through Canon's Virginia call center. Each service request requires a phone call to the center. This is because printers don't require service in some cases, but more importantly it is because in cases where your imagePROGRAF printer does require service Canon wants most likely applicable parts in the hands of the services technicians immediately. On the following business day after the service call, Canon's trained technician will come to you, together with the parts Canon believes are needed.
In most cases repairs are solved on the spot, and if additional parts are needed you're backed by Canon's professional ability to have everything immediately for technicians; delaying things one extra day is the rare case.
There is no "printer exchange program" with these largest of Canon's professional printers.