When somebody is in the final stages of dying how long does the "resting stage" last?

my grandpa has been steadily declining for the last 2 months, and now he is completely unresponsive. Hospice has told us to stop all medication, that he is in the resting stage of dying. he has not ate or drank anything for days and his urine is dark reddish brown. His breathing has slowed to 1 breath every 10-15 seconds and they are like gasping breaths, his heartbeat feels very irregular, like beat beat beat...........beat beat...beat beat beat.......Please let me know if anybody has experienced this, we are all so emotionaly exhausted and just don't know what to expect.