Hey there!
I am an equestrian but riding with only 1 THR at the moment. My right hip will need to get done in the next couple of years. I do know quite a few bilateral hipsters, and honestly the recovery was a lot easier on them, then those we went through with just the one THR.
The biggest theme I have noticed in those have gotten their second hip and got both done at once, is very tight PSOAS and hip flexors in general. If you can tolerate it, I would start working now on doing stretches daily and a couple of times of day if you can. That will help you post op(and do those post op when you are at a stage when you are allowed to do them).
As for getting back on, my surgeon and many equestrians have been told to wait at least 3 months before getting back on. It is such a demanding sport and can put a lot of stress on the joint, you want to make sure you give your body plenty of time to heal and mould to the new joint before you put stress on it. Of course always follow your surgeon’s advice before anything here, but these are the general guidelines I had to follow and know many fellow equestrians also had to follow. Three months in the grand scheme of things is nothing. You will be so busy getting yourself back into moving and exercises, that it will come to that date a lot quicker than you realize.
I do stretches every morning and at night before going to bed. If I don’t do them, I run into issues really quickly. Good luck with this journey! Can’t wait to see how you do! This is a really exciting part of your journey!