Many of us also went many years without a diagnosis. I'm not a vet so I can't help you on that question. What I can do is to encourage you to maintain movement as you age. The TNF blockers (Enbrel Remicade etc) do assist in the process of slowly disease progression. On this issue, you may want to consult with a Rheumatologist if not already seeing one, and working with your doctor to determine best treatment if any is best for you. Aside from the questions of benefits which you may be entitled to, make excellent choices about treatment.
I flew as an RN medevac in the Arctic, and spoke with the older guys who initiated the advent of radar in Alaska. Pretty cool science.