In California, does your permit have to be signed by a Driver Training instructor for the 6 months to start?

Since you have to wait for 6 months to get your license, does the 6 month countdown begin once you get your permit signed by the driver training instructor or is it when the permit is issued to you at the DMV? I need to know since I may not be able to do my first lesson of driver training with my permit since I will be out of town for about a month.