Postgraduate and specialty or GP training in the UK is the most important and penultimate step of a doctor in their career. It's every doctor's dream to be trained in some specific specialty, maybe in some specific region too. Life starts to get complicated with responsibilities and priorities regarding family and all when you reach that age and that's how a lot other factors start influencing the career choice too. That's why I would suggest to gather as much info as you can before you reach that point.
Where is the start of the . . .