There is much more than ACE required. It is already publicly stated that the 780g is NOT the pump which will have Tidepool integration. It is true the 780g is developed however the clinical trial is only now getting underway and AFAIK is not yet fully enrolled.
I still think @Nickyghaleb projection of 3 years is quite realistic although I feel that a slip to 4 years would be very likely.
Perhaps at some point Medtronic will decide to provide a concrete timeframe with a month and year. I think they probably will not. Ultimately, time will tell.
I am not randomly guessing but rather using timeframes that I see from various companies in how long they have R&D to Market. I consider this to be an educated ballpark approximation. And am sticking with 4 years for my ballpark.