You can generally tell if you've had a liver dump by using a glucose meter to test your glucose levels at bedtime then again in the morning after you wake up - you'll see a rise in the 2nd reading. I may see a rise from overnight if I test before I get up, but my "dump" can happen instead after I've been up and active for a bit, so I sometimes see one after I'm up, washed and dressed, and am checking just before I eat breakfast.
This morning "high" is often the last level to get reduced when we've been working to improve our glucose levels - and the hardest to fix as we have the least control over it.
Robbity