Hi. I'm 70 and I had RALP in 2016. I run very regularly: I've run two half-marathons this month, while last month I ran a marathon and 2 HMs.
I had severe urinary incontinence for about 8 weeks post RALP (which was very disappointing) then it improved almost overnight. For the past several years I have only had to use incontinence pads when hill-walking (steep rocky descents at the end of the day are just too much for my poor remaining sphincter to cope with).
Regarding running, for the first few years I only ran in the morning, before breakfast, when my bladder was empty. This was not a big deal as I love doing that anyhow. But eventually I plucked up the courage to do some evening races and I can cope without leakage on evening 10ks.
Regarding HMs and marathons, these tend to have a morning start anyhow and I try to ensure I start with an empty bladder and take sips as I go along to avoid over hydrating, and I generally get by without continence problems. I certainly would not use a pad for anything other than hill-walking.
Hope this helps. You will soon be able to race in the 80-84 category where the age grades are so much easier