Will all hairs from a graft start growing at same time and grow at same pace?

Transplanted hairs generally fall out within the first few weeks after surgery.  Transplanted hair start growing within the first few months after surgery.  Transplanted hairs do not immediately start to grow out after it falls out.

I am not much into counting, just watching the impact of the graft growth. Yes, the individual hairs do grow at different rates, but they grow, and it does not make much difference which comes first as long as they all grow. Focus on growth and you results, the indeividual hair will take care of themselves

Hair normally goes through cycle of growth.  It is a mystery how this cycle happens but it does happen.  we lose hair every day as hair follicles go through their normal cyclic activity of anagen (growth phase-90%),catagen (shedding phase), and telogen (resting phase-10%). The average number of scalp hairs lost daily from a full head of hair due to normal catagen activity is up to 100. Hair loss due to this typical cycling process is considered normal, as it is the amount of hair loss a person is accustomed to seeing. Over the course of several cycles, this normal hair loss is recognized as temporary, as the lost hairs will be replaced by new growth.  After hair transplant this intrinsic cycle of hair continues, thereby resulting in gradual growth of hairs transplanted.  Each hair has its own cycle and therefore depending on where in the cycle it is, then it will goes through its normal process after the transplant.  Therefore you may see some growth after three moths and it may continue to grow in up to 18 months after the procedure.