I ordered my 763 from a hidden page when it said there was only one in stock, and it showed up...
Does this mean you received your rod? If so, that's a unique way to place an order. Nicely done!
I did receive the 763. When I saw the thread that they weren't on the website I did a couple of web searches and one of them was a "shopping" link that I normally would ignore, but tried anyway. Sure enough, it went to the hidden page, and when I clicked on the 763 it showed "1 available" so I ordered it. It shipped the next day and got here a couple of days later. Shockingly, the box was torn open on the end and the rod tube could have fallen right out, but didn't!
I was also able to select the 764 and place a back order with a May shipping date. The page shows two of the 8.5' 6wt rods available. You can also select and place a backorder for the 8'5wt rod, but no other versions.
I have a theory, and only time will tell if it's correct. I was considering ordering one of these for the last month or two, so I was watching the page. Before they hid the page they were taking back orders on several models that weren't in stock. The shipping date was the same May date I saw when I placed the order for the 764. Over time the ability to place back orders has disappeared on different models at different times. The only thing that makes sense to me is that they have a planned run of rods to fill the backorders and they stop allowing them to be placed when the quota is met. That would let them make one run, cover all the backorders, and move on.
I called Orvis to ask if they thought my backorder would be filled and they were pretty surprised it was even possible...that was almost two weeks ago so they've had time to shut things down if they didn't want backorders.
If I'm wrong I would think they would know about all the backorders and send out notice that they can't be filled and maybe offer to be put first in line for the updated models, or something like that.
Time will tell!