When I was fitter I used to do the same sort of thing as you do now. The only thing I would add is some physiotherapy exercises. Set yourself a 30 minutes exercise program every day.

If you have no experience of physiotherapy then perhaps get to be seen by a physio. Pay if you have too but the one session should be enough for your needs. Learn the exercises she shows you and remember the once that she thinks suit you best. Then find a time of the day that is best for you to do the program. In my case it has always been an empty bedroom with the radio on early in the morning.

Once you find the right prog. of exercises and the place to do them choose a time of the day that you can stick with it. This is a long term thing so get it right and then it will just become an ordinary part of your day just as natural as say brushing your teeth. Keep up your swimming as it is the best all round exercise you can do.

Re. your remission, make the most of it as you are right it may or may not last forever, probably not. I have had various remissions over the years. Mostly they lasted a few months but I did once go for 20 years with virtually no A.S. symptoms. It come eventually to an end and now I am worse than I ever was.