In late June my CRS said I was healed. And if I had mild pain just throw some nifidepine on it. Anyway I still have mild discomfort here and there. I also noticed either a sentinel pile or hard edge around whethe the fissure used to be. Can this be causing some of the mild discomfort?

Well, I have not been the same since my huge AF of Dec, 2012. Big sentinel pile outside, sometimes a crunchy sensation inside...definitely dealing with scar tissue! Others have said the pile fades with time/improvement. I'm still waiting. I'm hoping these residuals won't lead to a re-tear but I do think it's a risk factor (have been told as much by physicians) and reason to continue to be careful!!! So, for example, I went on my easier walk today rather than the more uphill version, after a couple of rough days. Best of luck!

Yeah stupidanalfissure
That hard edge can be your sentinel pile which is also called a skin tag. I had them and they all cleared up on their own.
Now, your job is to keep your stools nice and sentinel pile friendly sort of speak. Give it some weeks into months of smooth sailing "down there" for the irratation to cease.
Irritation down there can occur without the piles just from a healing fissure so its nothing to be too concerned over. Even a little blood in the stools is not too uncommon, just in case you encounter this.
As long as there is still scar tissue and piles/tags, irritation and discomfort will happen. By gosh, it takes quite awhile for all of that to totally clear up so that's why due diligence and patience is in the order.
GL