Is Supprelin Implant Advisable After The Age Of 11?

My daughter is on supprelin implant for central precocious puberty. She will be 11.5 when the current implant expires and needs removed. I know commonly the meds are stopped at or before age 11. We are wondering if there is a reason to NOT continue it. While she will be 11.5 when removed, she is developmentally delayed and more like an 8-9 year old. If we did the implant until 12.5, it would then mean suppression meds would be stopped at a time when her chronological age matched her bone age. Seems like a logical time to stop, not just arbitrary that most kids we stop at or before 11. This would mean not starting her period until 13-14 years old when she would developmentally/intellectually be more like at least 10. Seems more doable. I know there is a risk she will break through suppression meds and a risk the supprelin can stop bone growth. So far, neither has been an issue so we d be willing to take our chances on that.