Hi Mike
This a question a lot of us ask and my very first post here was similar. The fact you're asking, I'd say you're not far away at all. Keep in mind that if you leave it too long, resurfacing can actually no longer be an option. I think it's due to the deterioration of the bone quality.
As a fellow squash player, with a high threshold for pain, I'd give you this advice based on my experience. Don't leave it as long as I did. I waited & tolerated pain way too long. Although I was playing squash up until 3 weeks prior to my BHR, I was taking diclofenac & codeine so I could play. I would sometimes pay for days after, also impacting my sleep so was taking sleeping aids to boot. All these meds had there own side effects.
Long story short (if you want the long, refer under hip resurfacing stories), I am back playing squash now & have been since 11 months post op. I take no meds & enjoy an active pain free life. Although I did just blow my calf again on the court!
Your comment about having the op earlier Vs later so your recovery will be better, is an accurate one. The stronger & fitter you are going into the surgery better. Do strengthening exercises as much as can on you bad side prior to the op, incl core exercises. Also work on upper body as this will carry you around for first few weeks whilst on crutches. It'll give you a good head start post op.
I think part of my delay was because I was only in my early forties. I found it hard to swallow having a hip op at this age, but I have no regrets at all. If/when my other hip needs doing, there's no way I'm going to wait as long.
Good luck & keep us posted on your decision. Make sure you get an experienced surgeon too, i.e.
at least 500+ resurfacings under his belt.
Cherz
Simon