Sorry if this is well-trodden ground already discussed elsewhere (I was unsuccessful in finding anything relevant in a forum search), but what is the deal with DL-AZ codeshares on TATL flights? The only DL-marketed nonstops I can find (via delta.com and ITA Matrix) are all on DL metal. (Interestingly, however, I can find AZ-marketed but DL-operated flights -- but not in business class -- when searching via ITA's website.)