Well, my BG did suprisingly well for this.
I started with a 20% basal reduction around 3pm (I had had 20g carbs for lunch but also did a walk so didn’t bolus). By 7pm when the real fun started I changed to a 30% reduction, set for 14 hours. I was 128 at bedtime and had a just-in-case juice box. I did not get much sleep (TMI) but around 4am notice my BG was down to 95. Since I usually drop in the morning I cancelled my temp basal and started a new one with a 50% reduction to avoid having to treat a low before the colonoscopy.
By 5am it hadn’t come up as much as I’d like, so I suspended the pump for about 90 minutes - was 146 right before the procedure, and 112 when I got home.
As everything is still passing right through me (TMI again, sorry) I am being very conservative with my boluses, and only covering about half of what I eat. I still hit 50 in the middle of the afternoon, but since then it’s been more like 140.
And BTW it took me almost 4 hours to down the 8 glasses of gunk last night - the first 5 were right on schedule every 15 minutes, then the last 3 took like 45 minutes each to choke down. Not fun - but a necessary evil, I suppose. Good luck with yours, Danielle!