Excellent! You've already got your corrective movement!
I assume you are doing this 10 repetitions, every two hours? (so 8 or more sessions a day)
How long does the relief last? You may need to do it more frequently for a few days: for example, if relief lasts for 35 minutes, you may need to do the movement every 30 minutes, etc.
The more time the bones spend lined up right, the faster the collegen your body is throwing at the SI can get it stuck back down. It's like spiderweb. You don't want to stretch or tear it and you want it to build up.
It may take a while and a lot of work, but if you can chase it down and keep it symptom free for a week (that means in place for a week and doing your corrective movement that entire time) that is about enough time for the collagen to build up. It may take a few weeks to get to that point.