I don't want to bother everyone with all the details of my situation again but I wasn't particularly sedentary when my flare started. I had been however pretty anxious for a few months before and I had made major changes to my diet and lost 20 pounds in 4 weeks or so. I don't know if that could be brutal enough to trigger a flare.
Mid-May to Mid-June: flaring, about 7/10 pain level Mid-June to Mid-July: flare calmed down to a manageable 3/10 pain Rest of July to second week of August: flare went back up again to about 6.5/10 pain Mid-August to now: flare went back down to about 4/10, manageable
I had blood work done at the end of June and everything was perfect (I'm usually high CRP when flaring). My range of motion tests all came back great so that's it for me. Waiting for an MRI appointment that takes forever. For the time being I'm just enduring my flare.