All manuscripts are edited in the order that they are recieved, and there are no price increases for quicker turnaround. All effort is made to return documents as soon as possible, and in the past three years the longest one of our clients had to wait was 7 days. Most manuscripts are returned within 2–5 days, including weekends.
If you have specific deadlines that need to be met, these can most often be accomodated. This is especially the case for re-editing and for checking journal proofs that often have a 48-hour deadline.