I believe in some cases it only took a couple days when there was "a rush" put on it. Not sure if I seen less than that though.
They may or may not have DNA results back at this time. And, I speculate that because the crime scene area was rather large and outdoors where there was likely a lot of evidence gathered, it may take extra time to analyze everything they collected. Once DNA test results are complete LE will not necessarily reveal them publicly.