Sorry no one responded!
In future, rather than give HC dry, you can add some honey/karo/syrup to LC food to increase the carb%
I see he was 77 an hour later? Can you stay up and get a test in another hour? You want to ensure his numbers don't drop again after the HC wears off.
He has earned a reduction by dropping below 60 on the AT. You would go down to 1.75U from tomorrow.
Btw, could you please edit your signature to say that you're using the AT. Thanks!