<p>After you've submitted your app for EA or ED, and then you get deferred, can you change/completely rewrite your app anyway you want and submit it again for RD? Or is it unchangeable once you submit it?</p>
<p>You can send updates like additional awards, etc. But you cannot change things like your essay, once submitted, you can’t edit your app.</p>
<p>If you are deferred, take it as a sign that they are looking for something to push you over the edge - Grades, another EC accomplishment, another SAT II test, … something. Make sure you write them to tell about your new accomplishment.</p>
<p>You can’t change your application, but being deferred is better than RD - at least you are almost there.</p>
<p>Maybe it’s just me but I thought a deferral from ED just put you into the RD pool, so it pretty much IS RD (with the ability to update grades and ECs). I don’t see how that’s better than being RD since you are still competing for the same slots.</p>
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Because they haven’t rejected you outright. At least you know you are in the pool of students they are seriously considering.</p>
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You can only conclude this if you know the deferral rate. Some schools, like Stanford, are honest with applicants. If the scores or class rigor or GPA is such that they know you are not a competitive candidate, they reject you in the ED round. Many schools, however, have a practice of deferring just about everyone who applies ED. Now perhaps it happens that just about everyone who applies ED to these schools actually is a competitive candidate and is still being seriously considered. A more likely explanation, IMHO, is that they’ve found it more expedient to let applicants believe they “still have a chance”.</p>
<p>^That or as courtesy, such as not outright rejecting a valedictorian.</p>