Not sure of the exact dates. I sold for a company that was a dealer, around 1986. Company reorganized after some internal issues, which is when the "new" birdview was born and did not live long. Originally issued their own unique hardware, not compatible with other brands, then came the "High Block" LNB, the change in the positioiner so any IRD would work, and they hoped it would save the company.
The story I was given by the dealer who was deeply involved was that the company "over engineered", (which is why the dishes still survive) and they did their own trucking, too! Part of the problem was COST to get dishes to dealers...they couldn't be broken down for shipping! Of course, you can't rule out bad management, either.
Wish I could help you on the dates......I know only of my time in it, and my ALWAYS wanting one....back when I sold them, they were 2 to 3 thousand, and the "best" of the best in the industry. We used to go out and literally "sit" in the dish to show the durability...and yes, the dish stayed aligned.
Sorry for boring you....