So, my current unproven thinking is that the specific inflamed painful sores are basically butt acne.
On that basis, perhaps shower before and after rides with a salicyclic acid facial wash, make sure your shorts are insanely clean (consider all of machine, vinegar soak, and hand wash) and get out of them ASAP after each ride.
That said, every idea I could think of hasn't quite eliminated the one that developed over the past few weeks. Tomorrow's metric+ ride may be... interesting.
If you just mean general rawness and irritation that heals in the following days, that's not saddle sores but merely saddle soreness - for that, yes, bring chamois cream to re-apply. You can get the foil packets, I personally squeeze the big tube into emptied out and carefully washed 1oz hand lotion sample tubes (gold bond, etc) to bring on rides. And consider something like hand lotion, bag balm, A&D or whatever after your post-ride shower.