I am trying to create a new cached basemap and I didn't realize what the different tile formats meant for my cached basemap. The cache defaulted to MIXED, but I would like to set it to PNG32 instead to improve the quality. Whenever I go into my service properties, or try to republish the mapservice the Tile Format field is greyed out. Is there a way to change the tile format when I refresh my cache or do I have to delete my cache and recreate it in the new format.