I was diagnosed with one a couple of years ago and it also came just before a big event I had entered.
I was able to use a private consultation via work cover to get to see a surgeon quickly. Expecting the worst, I told him about my plans and anticipated he was about to tell me I couldn't do it.
He then pointed out that if I was on the NHS I would likely be waiting three months for an appointment to see him so would not have been confirmed in any case. Effectively, it may get worse from the ride, but could easily have done the same without me being any the wiser. His advice was therefore to just go ahead and do it.
I ended up not having he operation until the following year.