Given the restaurant is new, and everyone wants to eat there and the time of your ADR- I think your chances are pretty unlikely that you will be able to be taken early. We have lucked out getting in early for ADRs for the early time slots of the day. So, if the 1st time slot is 5 PM for dinner and we have a 5:30 ADR we have had a couple restaurants (Chef Mickey, Crystal Palace) seat us at 5 PM when we showed up. This is the exception- not the rule.
I would say the later into the evening you go the longer the wait- as they have begun to back up. Longest we have waited is 1+ hours for LTT and approx 1 hour for H&V (never again for either- or any restaurant for that matter) both ADRs were for in the 6 PM range and we were seated approx 7PM.
I would say either just plan on going and not stressing and have a good time, or cancel and go for lunch at BOG instead- especially if you were looking forward to checking out the new place it's CS and your chances of timing it right and getting in are great, especially f you are a seasoned WDW planner. You can also try calling back every day to see if something earlier opens up. It can happen.