It raises both TA and CH. It is possible -- with a sand filter -- to use cal hypo so that, once the pH + CA + CH are at saturation, the rise stops.

You're not at that point yet. But if you add cal hypo via the skimmer AND let your pH float, it will stabilize near saturation. This is not a great idea if you have a heater, and MUST not be done if you have ANY sort of feeder or chemicals ANYWHERE between the skimmer and the filter: cal hypo tends to react VERY BADLY if it comes into direct contact with any number of other chemicals, including forms of chlorine.