Thank you guys. Working on it or investigating is going to be a week or two out. We're under 10" of snow, and it's currently -3F. I suspect there is a good ice layer on it now. Last time I was pumping the cover and looking under it was in the mid 30's.

As far as I know, I don't have a bottom drain. I'm assuming it would be plainly visible, right? The hopper of the deep end is smooth. I think at this point I'm below the suction and return lines as well, unless I totally misjudged the depth in the shallow end. I guess the best I could hope for now is an issue mid depth, at least the water will drain to there and not be totally empty.

Barring that, any ideas what else could have happened? I'm just shocked at how quickly I lost the water. I added 2x over the summer, but figured without a solar cover, a dry summer, and kids in and out constantly, that was par for the course. At this rate, it would have been empty by mid summer. Can a liner just catastrophically fail somehow? Anything that the closing company could have/have not done correctly?

Thank you for your help!