Look at it this way:
Dippers 8/26
QPR 9/1Stoke 9/15
In two of those three matches, we should be fine without him IF he has to be gone that long. Based on his tweet, I'd guess it might not even be the case at this point. Let's wait and see how tomorrow goes for him.
On the other hand, if he is in a longer recovery spell and he is "close" or on the verge of returning or whatever before we go to the Brit, I'd hold him out of the Stoke match. No need to have him run over by some big lad and back in the training room. If necessary and the timetable dictates it, hold him back until Arse at ours on 9/23.
Regardless, Carlos looks on good form and I'm sure him and Edin/Mario can do the business until Kun returns. I'm surprised to see all the complaining going around here about Aguero being so indispensable. If we only have one worthy striker on this squad (which we don't), then God help us trying to repeat as champions, let alone Cups and CL.