When you shot late yesterday morning, was your PM shot 12 hours later? If not, what you were seeing this morning was the effect of the overlap between a late shot and an early shot. When you shoot late, your next shot should be 12 hours from your last shot time.
The other possibility is that Sophie is dropping into lower numbers over night and some mornings, is bouncing up into higher numbers. You're not testing during the PM cycle most nights, so you don't know what's going on. You may want to consider getting PM tests more often.
If you are routinely having to skip shots or miss shots, it may be helpful to reduce Sophie's dose so you can shoot the same dose twice a day. Splitting doses (i.e, giving part of a dose at pre-shot and then giving more insulin a little later in the cycle really is not a recommended strategy. It causes any number of problems with the nadir and overlap and can contribute to having difficulty with managing low numbers.
