The BBL performed in the right hands with a good technique, will give you permanent Results, you have to know that we are working with fatty alive cells, if they get enough bood flow, and nurishment, they will survive and will get attached to the buttocks, in the process of the transfer 30-40% of this cells will absorb because that percentage of cells dont get enough blood flow. The injection is important to have a good distribution of fat in the area for better results. If you want to have a second round of fat grafting I suggest at least 3 months to touch your buttocks again, and if you want to use fat from the same areas (donor site) we have to see if you still have fat and wait 6 months, or use other areas like arms or inner thigh. What I like to do is to put more fat knowing that you will have an absorption of 30% and just have one procedure that reduces cost, and recovery time.