I agree a result date isn't strictly needed, I just think it could be a useful way to have a clear point in time from which to discuss the results, mainly one that is not too early.
As far as consensus changes after that point, I agree they shouldn't be ignored. I almost said similar things in my original comment, so I'm glad you brought this up. Instead of calling it a determination date, maybe it's better to phrase it as an initial consensus date.
"Initial consensus date" makes sense. It is somewhat similar to having a delayed start date on funding, to give people a chance to get votes in place first.