Very nice. Now the question is whether he will continue to drop or when he will start back up.
If he starts back up and is above 160 or so at pre shot, I would try the .8 again, if you can monitor. If he bounces up to 300+, you might try one unit as he would have had enough room to go lower today for that type of pre shot.
If he continues down and is still dropping by pre shot, then I would be more conservative. I wouldn't shoot unless he is past +12 and rising and then maybe .5 on the 160-180 if you can monitor.
I am thinking ahead as we are leaving for the weekend. I will have my phone but it is harder to response with and I usually can't see spreadsheets. Carl and Jenn will hopefully help with doses also.
You are doing great, Kathleen. I am astounded that he is responding so well after so long on insulin. I am sad, though, that if your vet had encouraged testing more often in the beginning and given you more guidance, he might have been in remission long ago……….