I am interested in the ATRRS Ordnance Officer Branch Qualification in order to be diverse and a successful XO. What are the pros and cons?

CPT (Join to see) ordinance = municipal law. Ordnance = a kick ass Army Branch that plans, executes, and manages maintenance, ammunition support, and EOD.

I think the course title you may have yanked off AtRRS is probably the officer basic course for Ordnance Officers. Once upon a time there was a two week transition course for branch detail and branch transfers. This was taught at the OD Center and School and the regional professional training centers like the one at Camp Robinson AR.

What is the course description and requirements? I believe it will be OBC or what ever BOLC they call it.

What you would really benefit from is a motor officer course if that is available. Sometimes it was called the Battalion Motor Officer course. The RC may have a locally developed course. The BMO course taught you a lot about running a Motorpool and a co/BN maintenance program....TAMS in the olden days. It also taught you how to work the supply system through the magic of a 4086 Burroughs TACCS box. All this is now different iterations of GCCS-A. SAMS E is probably in progress of being absorbed into the G Army Borg collective. If there is a G Army course, that will pay great dividends for you, as the XO you will likely have to manage the supply and maintenance areas which are both on G Army for supply, maint, and financial.

LTC Jason Mackay is correct in that you're looking at a course for branch detailed officers. Here's what the ATRRS description says about the course: "Web based distributed learning interactive courseware designed to provide officers newly branch detailed into Ordnance maintenance or ammunition Area of Concentrations (AOC) with an orientation to Ordnance assignments. It also provides the officer with the necessary tools to successfully function in a variety of Field and Sustainment Maintenance assignments by providing training in maintenance and related supply functions."

I'm not sure that they will let you into the course without being branch detailed. You can always ask though. Having a second AOC certainly won't hurt you.

This is in addition to my Signal Officer QUAL.