<p>These come in at least three ‘flavors’ with different triggers.
One comes to those that mentioned special learning challenges or disabilities,
mostly asking about needs and requirements.<br>
One comes if you had special accomplishments and focuses mostly on that.
The last type is for the small pile on the fence between accept and reject, and may focus more on academic history and the like. </p>
<p>It is good to get a request unless you are certain you are a guaranteed ‘yes’. </p>
<p>It means that your odds are probably better than even.</p>