I got a call around 10am this morning asking if we were still interested in her. I told her we were and we would come by this afternoon to pay for her and finalize the paperwork. She called back 15 minutes later to say her manager said she couldn't be spayed on Monday because that was technically her 7th day and they would have to wait until Thursday. We said we still wanted to come and visit today and pay for her.
When we went there and paid for her ($181 for adoption fee, 6 months of heartworm and Advantage meds, rabies shot, spaying and lampshade collar) the same woman reiterated we would have to wait until Thursday but that we could come back and visit her again before then.
When we left after visiting and were only a mile from the SPCA, she called again to tell me her manager said she could be spayed on Monday and we can pick her up tomorrow at 5pm. Hooray new dog! I knew it would be to our advantage to show up today with cash in hand to adopt her. We've nearly settled on a name but are going to sleep on it and finish the mandatory Googling to make sure it's not the name of a Honduran stripper (unless our new dog looks like a Honduran stripper).