Hmmm not a peacock, its definately a mbuna. Exactly what i cant be sure. For sure not a socolofi. Ive never seen one with yellow. A side shot will help ID, but if its a hybrid you will never know.
You purchased it as a socolofi? Sometimes when fish hybridize thier fry will appear to be normal until down the line a 'weird' looking one will pop up. So, some people will be SURE thier fish are pure until they breed them and get a few funny lookin fry... which could be your case. They were sold to the LFS as pure because the breeder thought they were, but low and behold there are some crossed genes that they werent aware of. Happens quite often.
If your willing to make the trip you could take the fish back and get others, but if they are from the same batch they are all hybrids, whether they look like pure socolofi's or not. They will all carry the hybrid traits.
HTH
-Diana