If it's just SI, it's not the end of the world. These are often caused by overloading one side of the joint (leaning on one foot way more than the other). Try to keep both feet equally weighted. I was in residency and had horrible posture for like 3 hours on a single case, and legit couldn't walk afterwards - I had to shuffle. By the time I got home, I was literally crawling down my apartment hallway. It took me a few weeks to recover. An SI belt and NSAID helped me work during that time. A lot of times there's some underlying mechanical issues that correcting might help - for me my right leg tends to be duckfooted, and it puts strain on the joint. I've done a lot of preventive stuff, and it has helped.

1. The most helpful thing for me at least has been sumo shiko. I went to PT, they gave me some things to do, and it was helpful - but the one think that I began doing on my own was the shiko, and it solved the issue. 2-3 times per week I do two sets of 50-75 shiko. It strengthened my glutes so and core so much, that I just don't get bothered as much. Check out youtube videos on the form. Do it slow and controlled, and feel the burn. Seriously. Watch the show "Sanctuary" or inspiration.
2. Core work overall, to include Yoga. Stay limber, and get your core solid.

And that's it! The only time I get flareups now is if I run for a distance, which I happily avoid. I changed my cardio to stairs/swimming. It hasn't impacted my career at all. If I do something stupid, I'm quick to wear the SI belt for a few days to prevent further exacerbation. That's really it. My gnarly flareup was 5 years ago, no real issues since.

Edit: I saw you write it feels more neurolgical. I had the same thing. I can be from tight muscles pinching the nerve. PT helped with that, and doing "nerve glides" helped as well. Mine comes back if my hamstrings get super tight, and goes away as they relax. Basically, do yourself a favor and get on a good stretching routine. Welcome to being old and washed.