5 years, wow. You're a PE "old hat".
Most people's gains seem to stop after a certain point.
Questions:
Is 8.25" non-bone pressed erect length?
Has your erection angle changed?
Have you ever had an injury or pain?
What's your routine?
Use any tools ie pump, cock ring, clamp, Power Jelg, hangers, all day stretchers (like JES), etc...