ambiguity - Is "until" inclusive or exclusive?

I sent an email to someone and got an auto-reply saying:

I am out of the office until 09/15/2014.

Does this mean he will be available on the morning of the 15th?

Answer

• I am out of the office until 09/15/2014.

My question is, will he be available on the morning of the 15th?

Well, pragmatically, if that date lands on a Monday, then I'd think he would be in his office that day.

Let's see how the word "until" kinda works. For example, consider:

• 1) "[The man kept on kicking the bear] until the bear growled."

That means that when the bear growled, the man immediately stopped doing whatever action he was doing (such as kicking the bear). That is, if I were that man, I'd stop kicking the bear--but then, I wouldn't be kicking a bear to begin with.

So let's now tweak that so it's somewhat more similar to your example:

• 2) "[The man kept on kicking the bear] until 09/15/2014."

That means that when it became 09/15/2014, the man stopped kicking the bear. (Poor bear.)

So, now, with your original version:

• "I am out of the office until 09/15/2014."

That means that when it becomes 09/15/2014, the man will stop being out of his office -- which implies that he will be in his office (right then and there on that given date). And if he is normally at work in the mornings, then he probably oughta be there that morning--but who knows, maybe he'll be busy catching up with his emails and whatnots.

OH! LOOK! 09/15/2014 is a Monday!

Phew! It looks like my rationale is rational. Surprise, surprise. Sometimes it works out that way. (And sometimes it don't.)