I had a face-to-face meeting with the owner of the dealership today, and have a much better understanding of what's going on. Turns out that the shortage / bottleneck on these machines is a Kubota planning problem being aggravated by the Kubota allocation system.
The planning problem is that they under-estimated the demand for this machine ... badly. The allocation system problem is more complicated.
The "factory order number" I was told about last week doesn't exist on a machine when the order is placed with Kubota by the dealer. It only exists when Kubota assigns an actual machine to that order. In my case, the order was turned in by the dealer promptly, and they are still waiting for Kubota to assign an actual machine to it. Until that happens, there is nothing to track. They have a system by which the Regional Sales VP learns of the number of machines in the pipeline, allocates those to District Sales Managers, who allocate them to dealers. Until machines are allocated to a given dealer through that chain, no factory order number is assigned. My machine is still unassigned. Repeated calls to several folk at Kubota about the allocation /assignment placed by the dealer with every contact they have yielded nothing substantial.
The dealer has committed to take a factory stock machine (one of two due within "a couple of weeks" according to Kubota in GA) trade the 12" bucket for a 10", swap the turf tires for bar/ag tires, and retrofit the 3 position valve with the 4 position that I need. They are making a good faith effort to meet my needs, and are caught by a shortage in the Kubota pipeline (recent phenomenon, within the last 5 weeks) the structure through which allocations are made at Kubota, and the unavailability of key people at Kubota to return calls and help clear up the mystery.
So, net end result: I'm still waiting, and hoping for a machine that may arrive within the next two weeks. The only good news is that a machine for a fellow who ordered 4 weeks before I did is on a truck from GA to VA now. So at least some machines are moving, and someone is about to get one. Just not me, not yet.