That depends on your timing! We work from one volume to the next, and have a lot of other books to work on in between.
If you happen to send in a story that catches our attention on the exact day we’re compiling the list of stories for the next volume, we could be back in touch within minutes or hours. If you send in a story while we’re busy with other stuff, then it may be a while (weeks, or even a couple of months).
We’re always happy to be nudged, but please do understand that we have a lot going on.