General Practice has changed from the "old days" where you had one doctor working alone who was the only doctor you ever saw. Today, most practices work as a team. This is because a lot of doctors choose to work part time and also because of the nationwide shortage of general practitioners. We try to give an appointment with the doctor of your choice but this is not always possible at short notice. However, we try our utmost to ensure there is a doctor available on the day you ring especially if you have an urgent problem.
The advantage of a team approach is that you often get a different opinion or new perspective on your problems. The doctors all meet as a team and discuss cases, this is part of maintaining continuity of care. Your medical records are fully available to whichever doctor you see so they have all your information at hand.