there needs to be a lot more information provided for anyone to tell you whether those 3 letters means anything. for instance, where were these three letters found? did you request case notes? is this from the sponsor approval letter, a request from the visa office? we can't tell you what something means without some background information to go along with it. to get real advice, provide more details of what you want to know. we are not mindreaders and don't know where these letters are being referenced from.