Can someone explain the difference between the ST pathway and Academic (ACF) pathway after CMT/IMT?

Hello. Can someone explain the difference between the ST pathway and Academic (ACF) pathway after CMT/IMT?

  1. The advantages and disadvantages of each?
  2. Do you do a PhD or MD along with training in ACF alone, or can you do that with the regular ST pathway as well?
  3. I understand that ACF posts are for fixed terms, such as 3 years. But you don’t get a CCT in three years usually in most specialties. So what happens at the end of 3 years, do you continue further training to obtain a CCT or do you go into a PhD route?

Thanks in advance.