I could not figure out the meaning of this question. Could someone explain me briefly? This statement was in "answering audience questions" which is a presentation guide line.
This sentence does not appear to stand on its own, so context would be required to provide a better answer. However, assuming there was a transmission error, we have a few possibilities:
When will you be in Through?
Assuming that capitalization was forgotten, the asker may wish to know when you will arrive at a location called "Through."
When will you be through?
Assuming that the in doesn't belong, the asker wants to know when you will be finished.
When will you be in, though?
Assuming a misspelling and a dropped comma, the asker wants to know when you will arrive at your destination.
A possible meaning is that this question is asking for a period when the person will be "In" as opposed to "Out". When discussing a movie's run a a theater you can say that "Movie X will run through the Week of March 9" or some such.
So the question could be asking what period of days or weeks this person will be "in"