You might benefit from a “Green Light Laser TURP” (trans-urethral resection of the prostate) where they may also be able to remove some of the calcification at the same time. My mate aged seventy had it done, was in hospital just overnight, and he is now “pissing like a horse”, and his “erections are as good as ever”...
I hope you get your urology appointment soon.
Cheers, John.