No - nobody has said they think he has PDD (only understandable online reactions to the pictures of his poops). I said I was afraid it might be PDD to the vet, but she said that we'd see if he responded to the antibiotics first.
This all started in the late summer when I thought eating unripe strawberries was the problem. There were strawberry plants hanging in the aviary which he has left alone until this year. When he ran out of the red he started eating the green. Another thought is that it could be something he caught from outdoor birds in the aviary as he was out there every day. I do keep it washed down, but I could have missed something (it doesn't have a solid roof). This is the first time he has been on antibiotics for it. A few months ago his poops were sent off and results were negative for everything tested for, so I was told to keep an eye on him.
At the beginning of the year I happened to attend an online live webinar by Dr Todd Driggers about the latest thoughts about ABV and PDD. How that it is likely passed vertically from mother or father to the egg. Also that if a bird is highly sexed it can activate it if a bird already tests positive for ABV, which is another reason why we shouldn't encourage nesty behaviour. Along the same lines, Ollie was pretty highly sexed through the summer which I couldn't really do anything about (it wasn't directed at me), but it did cross my mind that it wasn't good re activating the virus (not that he has ever been tested for it).
I have known a couple of Amazons who had PDD - interestingly their first symptoms were lack of balance. Ollie's balance is fine. He turns circles with no problem on cue for cashews.