@Justin_Sherrill
Not sure I can explain it, but it completed successfully this morning during the normal sync job. I have since changed the download_concurrency back to the default (10) and have successfully done another sync with the policy set to immediate. Once done, I was able to patch some development servers just fine so looks like my issues is fixed.
Thanks to everyone for their input and assistance. I love this product and the community has always been so helpful.