Tonight is a combination of bounce plus no insulin. The bounce part is probably happening for two reasons. First the low numbers, and next the fast drop at the beginning of the cycle. She dropped 200 points in the first four hours and that can cause a bounce. You might try testing at +2 if you can, and if you see a significantly lower number thenC, try giving her some food. You'll have to experiment to see what works best for Clare, whether it's low carb, medium carb or high carb. It depends how carb sensitive Clare is. I don't know when you feed her, but spreading meals out over the first few hours can help. If you are doing that already, then maybe something higher carb around +2 if she's dropping then.
I don't know about keeping them over 70, but if you can maximize the amount of time they surf the greens, then her liver will get more used to spending time there and bounce less. Slowing the drop as above, and feeding a little low carb food when they first hit green can help them surf.