Her Majesty will never abdicate. She considers her role as a sacred contract. Her faith is very important to her. If nature and time render her unable to fulfil her duties then Charles might serve as Prince Regent, but she will never abdicate. The memory of her uncle remains strong.
I’m aware of her steadfast refusal to abdicate in favor of Charles. I was more inquiring about her health and stamina, considering her age and relatively hectic schedule.
And Prince Phillip’s health is none too great either, as I understand it.