PH> If you run 'mis poll killbusy' but close MIS down first before you do 
 PH> Then restart and see how you go.

Thanks!  It turned out the central issue was my system rebooted in the middle of a poll, leaving corrupt stuff in my echomail folders (determined this by trying to unzip everything and a bunch of things would not unzip) which was causing Mystic to soil the proverbial bed.  As it crashed, it was leaving those .bsy files behind.  I cleaned out my echomail folders and now it seems to be humming along.  I am describing this here just in case someone else searches on the problem in the future.

I will remember the killbusy method in the future; I was using a for loop to find the files and rm them previously.

--- Mystic BBS v1.12 A47 2021/09/24 (Linux/64)