Whether it's legal would depend on your state's laws. First of all, a post-dated C-II scrip is illegal under fedeal law because C-II scrips expire in seven days and your doctor was flouting that law and allowing you to do the same. So your original doctor broke the law, and you too might be breaking the law if you fill that illegal first scrip. They could go after the doctor as well as you if they pursued it.

If you fill both scrips and your state has laws against double-dipping, you could get caught if your state has electronic prescription monitoring. So don't do anything that can get you in trouble. Especially if your state has a monitoring program for those C-IIs.

Trampy