My Neuro told me that I was most likely SPMS, when I stopped having
regular exacerbations. I have been SPMS for about 15 years now
and started progressing slowly but surely, from that point.

10 years ago, when I started LDN, my progression stopped and I
plateaued and pretty much stayed the way I was 10 years ago. I
have had heat and stress caused mini flares from time to time, but
with no lasting damage.

SPMS is the natural slower progression of MS for most RRMS Peeps.