That 125 yesterday was probably low enough to set off another bounce
They don't have to drop "too low" to bounce.....If they just drop into numbers their body isn't used to anymore, that's enough to do it.
Bounces happen when 1. they drop too low, 2. they drop too quickly, 3. they drop into numbers they aren't used to (or any combo of all 3)
Since cats are so good about hiding their diseases from us, usually by the time we get them diagnosed, they've been diabetic for quite some time. Their body gets used to living in those higher numbers, so even though he didn't drop into a "dangerous" number, his liver still responded like he had.
As he spends more and more time in "good numbers", his liver will hopefully learn that it's OK to be there again and he won't bounce as high and his bounces will clear faster