As you get older, and it can takes decades to steer the course, you might have ended up with a final concept and plan of action. It is honed down since everything else had fallen away. It is what is left and all that your thinking, pondering, and instincts have led you too. It is good that you have had such a final realization. Perhaps your nearing end has sharpened your awareness on finalizing the culmination of all your thinking.
So you have plan of action. Not all is known, there is room to grow in, but the parameters are set. The field to operate in is delineated. There will still be evolution and the unknown, but within this framework. Having achieved this is evidence there was meaning and purpose to all your questioning and searching.
On the other hand, with the years remaining fewer, part of you prefers not to strive and make things happen. You prefer to observe, to be entertained, to have others do the work and for you to be an onlooker.. This is no so much an intellectual process as rather your body and nature telling you what it needs
You can't maintain a strict regimen so easily. Indeed, often you can't be active at all and rather be passive and just see what just comes your way. You are almost as you were before you went on this long journey and quest.. Who knows, your path might have come out of pain and struggle. It might have made too many 'pure' demands on you while your soul yearned to just be a person, flaws and all. It's a one time chance just to be human with human needs. It's a chance to honor your frailty and not ask too much from life. You can have some fun, be pleasant with people and take the best from things without having to change them.
So while your striving has led you to a simplified disciplined existence to be played out, your inner life's cravings ask for a simpler recipe for old age. It is hard to know how this all plays out. Your biggest fear is to let down the vision you had and this might keep you from abandoning it. In between you might work in spontaneous life. This seems like a probable scenario.