Rescinding a Declined Offer?

[slimcat]

I know we often see questions here about rescinding an acceptance.  I was wondering if anyone had any experience or input about initially declining an offer, and then changing one's mind (in this case, within 24 hours of sending the email declining the offer).  I understand, of course, that my spot may no longer be available and may have been offered to someone on the waitlist. 

 

Thanks

[nugget]

I would do it ASAP without spending all this time thinking about form. The clock is ticking and you could lose your opportunity. With any luck, they haven't contacted the person on the waitlist yet, or that person will decline and the spot may go back to you.

[MathCat]

Definitely contact ASAP, but as you said, there is a (pretty good, I think) chance that the spot is no longer available.