I'm doing the drift align again now and I'm starting to think the periodic error is what I'm seeing.
I did drop the aggressiveness down to 70 from 100. I can't remember why I had it on 100 as I normally try for less.
I'll try to do a small adjustment to see if I can reduce the error further.
However, the RA line looks periodic.
Also, I'm pointing west, so I'll have to check east later. I have a suspicion the scope balance is affecting thing too.