In order to understand your dream might be trying to show you I need to compare what your waking ego apparently was doing last April and what your waking ego--or perhaps your "dozing-off" ego might be doing now. When did you begin to have this dream? And has it changed in ANY WAY(s) throughout your history of having it?
1. The FIRST contrast between what your waking ego was doing last April and what your "sleeping ego" has been doing in the dream is this: then you urged the doctors about "not prolonging his pain." But in the dreams it's a little different: "end his misery UNLESS they can save him." Yet your waking ego THEN and NOW KNOWS they can't save him.
2. So WHO might be able to SAVE him? We can ALL keep a deceased loved one WITH US (even without his actually being alive) in our imagining minds, that is, in our dreams or prayers, or inner dialogues. Could your dream-ego be keeping him alive--at Death's Door--instead of letting go of your special bond with him? I called your waking consciousness in recent months a "dozing-off ego" because when you slip out of your waking awareness that your "closest to each other" father is gone, you might easily "see" him as still alive, because he IS and always will be accessible in your imagination.
3. You remember when you're fully awake that "this is what he had asked us to do." But it might be really comforting -- when you "doze off" for a minute -- to "see" him "start breathing again" without you even (consciously) making it happen.
4. If my guesstimates about your waking, "dozing off" and dreaming consciousness are close to accurate, then you're wrestling with the need to accept his desire for you to let him go away from you, even though that is exactly what your daughter's heart that loves him as your first great love (tho you haven't said that you are female) doesn't want to do.
5. But you will need to do that some day, if you want to finish your long grieving journey through the dark of night and become ready to live in a world where he isn't ready and waiting for you when you doze off. And one of the great rewards for getting thru that grieving tunnel will be that you'll be able to love a person your own age and marry--and with that step you'll grow into a second great love that's much more difficult and maturing and spiritually growing than you could ever imagine as long as your father's love and pride in you was still "the best thing that ever happened to you."
These dreams are repeating, because they want you to make that forward progress choice that's what "he had asked you to do." 10 months is NOT too long to be holding onto his last breaths, not at all. 1 year is considered the normal grieving period all over the world. It's quite common in the waking world for a dying beloved to r3esume breathing for just long enough to say one last goodbye to the precious people who need that send-off. So write your father a letter to thank him for coming back to life so many times just to hear from you again: tell him everything you want to say now at this 10month time beyond his bodily death--and give him your blessing however feels just right to you.
Perhaps your next dream(s) will show you where to go from there. (comment if you wish)