Interesting ideas. I remember noticing a different perception of time when I started traveling to an annual weeklong festival that I attend annually in rural Iowa, where I spend much of my time outdoors with no clocks around to tell the time. I too, struggled with the dichotomy for a while. What led me to conclude the time continuum idea, however, was noticing that months, hours, and minutes remained the same each year despite the linear change of the year. I also noticed, when I started high school, that my life began forming a cyclical pattern of attending annual events that reflected the cyclical seasons of my hometown--a four season climate here in the Midwestern United States, and then, after finishing high school, a cyclical calendar of attending annual events. I experienced the perception of cyclical time in the form of these events that would appear in an annual cycle, but still felt the linear experience of aging and going from different stages of my life that did begin and end--in this case, from adolescence to young adulthood, which has had a linear trajectory.
Obviously, we are all different in our perceptions of time. I will say, however, as a person with autism, that time is a big part of the existence of the person with autism, since time governs so much of having autism, as your mind and body often run on a timetable different from many other humans.