You don't know how low she went last night.
The limited overnight data shows that she drops steadily throughout the night, right? She may have gone lower than she has been yet, and her body panicked, sending her into rebound, which is what I think the HI is this morning. We just don't know without data.
This big swings are not good. They make regulation harder and make the diabetic feel like crap (according to a human diabetic, who said he'd rather be higher and flat than swinging up and down)
I'm not sure why you went up to 2U when you did. She was doing very well on 1.75. Yes, you had that one setback due to your schedule, but it wasn't a good time to raise, in my opinion. Three days is a minimum settling period for a new dose, but that doesn't mean you automatically raise - if a dose is slowly bringing her down without wide swings, then you stay on it until
a) it isn't doing that anymore and it's time for another gentle bump up, or
b) she goes down in to the mid-green range, then it's time for a reduction.
While the decision is ultimately yours, it's a good idea to check in here on the board, there are lots of people going through the same thing. You guys are my friends, I'm happy to help, and I have experience, but I shouldn't be the only one with eyes on Callie right now.
For example, my own opinion is that 2U is too much, AT LEAST for the overnight cycle. So the idea I mentioned you y'all in an email - 2U in the morning and 1.75U in the evening might work. But I would love to know what others thought of that idea - do others use two different doses, or if you should decrease both doses or hold the course...
Meanwhile, continue to read and increase your own knowledge using the articles on this site - there is lots of good information saved as stickies at the top of this forum.
Maybe you could put dosing question in your subject line, and maybe a ? icon. Even if it's actually me with the questions! I would love to know what everyone else thinks. Also, as you get spot checks, add the numbers to your subject line as you get them, so everyone can see Callie's cycle as it unfolds.
Good luck!