Hi,
It would seem that you need a higher ratio at mealtimes, but having said that you'd need to do some fasting tests to be sure. It may be that your basal needs increasing too. So for example have a carb free lunch and test every 2 hours after to see what happens. But I would speak to your DSN first as you have only been diagnosed a short time and they may want to advise you differently, especially if the honeymoon phase is still in play. 1:20 is quite a low ratio so it's quite possible that it will need increasing. Get some advice first, and good luck.
Jo