Okay, I'll share my experience. The cervix will move lots during pregnancy, so how high or low it is doesn't matter. My cervix always started getting a little softer and a little more open right before my period, continuing to soften and open until right after ovulation, when it would get hard and close tight. When I was pregnant, it stayed hard and tightly closed until about a week before baby was born.
as far as cervical mucous goes, that depends on the pregnancy. With my first, I had what I'd call egg-white fertile quality mucous throughout my entire pregnancy! With my second, I alternated between bone dry and creamy cm.