I've recently applied for PhD programs in mathematics. I received an offer not long ago, and in light of this offer, there are only a few schools that I would consider an offer from. From past years results (and this year's), I expect to get results from two of them in the coming week, but another of them usually only sends out their final decisions three or so weeks from now (though they do, and have, sent decisions already to some applicants). I would like to make a decision fairly soon, and knowing about the status of my application at this final school would indeed make a difference in any decisions I make. When is it acceptable to ask them about the status of my application? Should I simply wait until they send me the result, or is it OK to ask earlier?
In more generality, so that this question might be useful to somebody that's not me: in general, when is it acceptable to ask schools about their admissions decision if they've not notified you yet?