Hi Kelley,
A number of things affect blood glucose levels, including:
* Food.
* Exercise.
* Effects of other hormones in the body (e.g. bouncing, dawn phenomenon).
* Infection or inflammatory processes going on in the body.
* Life.

(day to day variations in activity, etc.).
Blood glucose comes from:
* Food eaten (hence need to reduce carb load in diet).
* Glucose released from breakdown of glycogen in the liver.
* Synthesis of 'new' glucose in the body from reserves of fat and protein.
When a kitty drops too low OR when it drops to a number that's safe but currently unfamiliar to the body, its protective mechanisms can trigger release of stored sugars and synthesis of 'new' glucose to raise levels back to what it has been used to - sometimes overshooting to much higher levels. This phenomenon is referred to here as 'bouncing'. Bounces can also be triggered if BG drops steeply during the cycle.
Variations in BG are normal and to be expected. This is where the spreadsheet comes into its own: as you gather more BG readings it will, over time, help you identify Merlin's particular 'style' of response to food and insulin, but we only have limited options to try to mitigate other influences (e.g. feeding snacks at certain points in the cycle to slow fast drops and hopefully reduce frequency of bounces).
Mogs
.