You won't be able to get there before rope drop, but if you have an 8:10 ADR, I would think that you would have to eat pretty fast to get out and into the park by rope drop....even though it's a buffet, I would allow yourself at least an hour to eat at any TS....
As an aside, it looks like you're going around the same time as me and the crowd calendar levels are only 4 and 5's (with a stray 8 on the 16th), so I don't think you have anything to worry about when getting a TSM fastpass. When we were there in late September and crowd levels were low, passes were still available early afternoon. I wouldn't kill yourself or ruin your breakfast in an effort to get an earlier time.